Updated March 2022
Working with Routes, Tracks, Marks & Overlays
Part 4 of this parallel user’s guide covers working with routes and tracks and the rather unusual way of working with files that MM has adopted. This is a long post and apologies for that, but it covers some very important topics and if we don’t get these right we’re going to be on dodgy foundations.
Working with Routes
You will find that Routes are more flexible to change than tracks, but tracks are quicker to load into memory, especially if you’re creating lots and lots of routes, but we will discuss file handling later.
Once you get used to the system you will find that:
- Routes cannot be joined or separated, which is a damn nuisance. I am told that this is going to be fixed in a new release in the near future! UPDATE 27-01-2021: With the release of MM v6.4.0 this has now been fixed and you can split and join routes!
- Routes calculate the height gain, but tracks do not.
- Routes can be converted to tracks and the track will be an almost perfect replica of the route, but with that inevitable loss of control (because you can’t as easily amend a track).
Creating a Route
This is probably something you’ve already done, as it’s likely the first thing anyone does in MM. It’s also something that will become second nature as it’s at the core to everything you do in MM.
You can create a Route using either the menu option (Overlay > Create New > Route) or the icon in the toolbar.
Use this icon, in the ‘Standard‘ icon ribbon, to begin a new route. Nothing will happen when you click it, not until you click on the map screen. Your first click will drop and anchor a waypoint onto the map. As you move your mouse a blue (by default) line will stretch away from the locked waypoint and when you click on the map again, another waypoint will be dropped and anchored. By clicking like this you string a number of waypoints together into a route.
To complete the route either hit the ‘Esc‘ key, or double click the last waypoint. If you want to create a circular route, you can also complete a route by dropping your final waypoint directly onto the very first waypoint in the route. This essentially closes the route and although you now have a nice circular route is can cause some problems (see below).
Your new route will be added to the ‘Routes’ category in the Overlay Object panel, and it’s Overlay Properties will display information about the route, including the length, total ascent and descent and a list of the waypoints that make up the route. The short video below may help.
Two things quickly become apparent.
Firstly, you run out of map very quickly and you need to become adept at scrolling the map while the route tool is still selected. I have two main ways of doing this.
The first and least used is to use my left hand on the directional arrows on the keyboard and keep the screen moving in the direction of the route by tapping the arrow key constantly. This is logistically awkward (unless you’re left handed) because of the location of the arrow keys on a keyboard!
The second and almost exclusive way is to use the mouse wheel to zoom out and then back in again. This can be done while the route tool is active and with some practice can be really quick and simple. In the video above, you will note how I move my cursor away to the right once I reach the edge of the screen, I then zoom out, move my cursor back to the end of the route and then zoom back in, grabbing a new chunk of map real estate at the same time. This is a very effective way of creating ‘mouse-only’ routes – no need to use the keyboard here.
Secondly, once you’ve ‘closed’ a circular route by dropping you last waypoint onto the first waypoint, it’s very difficult to manipulate that route. You can’t, for example, disconnect that last waypoint and ‘break’ the circle. As such, my rule of thumb is never to close a route, and what I mean by that is never drop that last waypoint on top of the first. Just drop the last waypoint beside the first one if you’re making a circular route. See below. The route is ‘open’ and easier to manipulate or amend. Note: v6.4.0 has mostly removed this limitation, as you can now easily split a route by right clicking on any waypoint and selecting ‘Split Route’ from the context menu.
MM automatically names routes in incrementing numbers, so the first one you create is called ‘Route’ and the next ‘Route1’ then ‘Route2’ and so on. Each new route is given a new set of waypoint numbers based on the last digit of the route name (see section on Re-numbering Waypoints below).
An interesting feature added to MM v6 is the ability to auto-generate a route between two waypoints. Rather than manually clicking your way along a footpath on the map, you could let MM do the hard work for you. It’s worth pointing out that this facility requires an internet connection and has only limited knowledge of footpaths, so don’t expect too much from it. It seems to work quite well along National Trails for example, but less well (sometimes not at all) on those less trodden paths.
You can activate this by right clicking on your route and selecting Operations > Optimize Route for > Walking.
It also appears to be an ‘all or nothing’ route generator. For example, you can’t create part of a route manually, then try and get MM to auto-generate a section of the route between two waypoints. It will also only work on routes with up to 10 waypoints.
This a nice feature and probably one to watch for future updates, but for me right now it’s not serving any real purpose and I don’t use it.
Amending a Route
Once you’ve hit ‘Esc‘ or double clicked the final waypoint, or clicked back on the first waypoint the route is created. But what happens if you decide you want to change it?
We look at some of these option in more detail in a minute, but for now lets look at adding waypoints. Adding waypoints into the middle of a route is a bit of a faff, as each one has to be added individually using the right click menu for a waypoint, or by using the ‘Insert‘ key.
Adding waypoints to the end of a route is a bit easier. Right-click the last waypoint and the Waypoint context menu appears (shown on the left). Select ‘Add waypoint after‘ and this simply re-activates the route creation tool and allows you to continue dropping waypoints in succession, one new waypoint per click. If you find you need to add a bunch of waypoints to the start of a route, the best option is to first reverse the route (right-click the route and select ‘Reverse Route‘ from the context menu), add the waypoints to what is now the end of the route and then reverse it again when you’re finished. You can complete by re-numbering to sort out the waypoint numbers.
Now let’s look at the various options available to us once we’ve created a route.
Most of these can be accessed from the right-click context menu on a route. You need to click on the lines between waypoints to get this menu, not the waypoints themselves (that’s a different menu, see example above and more detail below). You will need to zoom in to the right level to be able to right click a route.
We run through all the context menu options below.
Follow route: is only appropriate if you have a GPS attached and will then show you how far there is left to walk and in which direction to go to reach the next waypoint.
Profile: this produces a side on view through the route, showing ascents and descents. Each waypoint along the route is identified with a vertical blue line. If you have named a Waypoint and selected ‘Show name’ in it’s Overlay Properties, then that name will also be displayed on the profile. I often find this useful for identifying the high point of a route, or a specific location like a pub!
As you move your mouse along the route (or along the profile itself) a red dot identifies its location and displays the distance from the start of the route, and the current elevation.
3D Fly-through: switches into 3D mode and then literally flies through the route. It’s very cool, but mostly completely useless. I’ve included a short clip of this as an example.
Insert Waypoint: does exactly what it says, adding a waypoint into the route at the point you clicked and allows you to select where to drop it.
Properties…: opens the Overlay Properties panel for this route.
Lock, Hide and Delete: are all obvious. If you lock a route, you also lock all the waypoints in that route. You can’t delete a route (or a waypoint) if it’s locked. If you do delete a route, you also delete all the waypoints in that route. You can Undo route deletion if you need. Hiding a route just removes it from the map, but the route stays in memory.
Sync to Cloud: will allow you to save this route on your MM account in the cloud. If you aren’t already logged in to your account on the MM app it will prompt you to do so and then it will send the route to your account.
You can view all your synced Tracks and Routes by logging in to your account on the web. Click the [My Overlays] button and select the appropriate tab. See screenshot.
We will cover syncing data in more detail in the mobile section of this guide. One thing to be aware of at this point though, is that you are allowed only 10 sync operations per calendar month, unless you buy the Premium sync package (about £9), which allows almost unlimited syncs. A sync operation is only counted to/from the mobile app, not from the desktop app.
Send to GPS: This option is probably greyed out, unless you have a GPS attached. I have never tried this option, so even with a GPS device attached I don’t really know what functions you get. Give it a try and see how you get on.
Send by Email: allows you to send a copy of the route in an email message. MM will open your default mail program and attach the route to the mail. Attachments are GPX files. This doesn’t appear to work with web email clients like GMail, but works fine with traditional email clients like Outlook.
Save As: allows you to save just that route to a file, all on its own. Useful if you want to save that route and not all the others that are currently in memory. We cover working with Overlays later. Files are saved as GPX by default, but you can choose to save as CSV, SHP, LOC or MMO file by using the ‘Save as type’ option before you click [Save].
Digital Map Shop: opens the DMS in the context of your current location and map. This would allow you to buy a map that relates to this location if you needed to.
Options off the Operations Menu
Print Route: The purpose of this option is obvious and I cover printing in a later section of this guide.
Route Card: Exports the contents of the route to a Route Card. A route card is something walkers may use to summarise the route they are taking. Route cards have multiple purposes and there’s loads of information available online as to why you may want to create one.
The template of the route card is stored locally on the PC and can be edited to suit your own purposes. The output format is HTML, so it opens in a web browser and can be printed from there. The default location for the template is C:\Program Files (x86)\Memory-Map\Navigator-6\Route_Card_Templates\Routecard_template.htm (this will be different if you changed the install location).
There is a settings dialog panel for the Route Card, located in the Overlay Properties window for the route (see below), which allows you to change the average speed, and adjustments for uphill and downhill speeds.
Convert to Track: is obvious. The route becomes hidden when converted and the track appears in its place, but you can always restore visibility of the route later if you wish.
Reverse Route: is also obvious, but although it switches the direction of the walk route, it doesn’t re-number the waypoints, so the last waypoint will now be number one and so on.
Re-number Waypoints: This option reviews the route and re-numbers the waypoints from 1 onwards. If you’ve reversed a route or added waypoints into the route then this is a good way of resetting the numbering. Strangely, if your Route name ends in a number (for example ‘Day 16’) then the renumbered waypoints all start with that number, i.e. WP1601, WP1602 and so on. Another oddity is that the numbering of waypoints isn’t logical; in this example, the 99th waypoint would be WP1699 but the hundredth would be WP16100 and not WP1700 as you may expect.
Enclosed Area: Leads to another sub-menu, the items in which are only active if the route you’re using is ‘closed’ or circular. You close a route by making your last click of the route on top of the first waypoint for that route. Unlike all other route waypoint clicks, this will end the route and you don’t need to press the [Esc] key to end the route.
Off the Enclosed Area menu
Export Map Area: This option only remains to support legacy Windows CE devices. It used to save the map area, inside the route, to a QC3 file of its own. You can now do this directly from your mobile device.
Save Enclosed Marks: This option lets you save all the marks inside the route into a separate file. This is one way of capturing a number of marks on the screen, perhaps cutting half a dozen hills out of a much larger selection.
Optimize Route for: This option auto-generates a route based on a couple of limitations and was discussed earlier in this page.
Download Map Along Route: This appears to allow you to download a strip of map that covers the route you called the menu from. As I have the full UK map loaded it doesn’t really work for me, so you’ll need to experiment to see how useful this is.
Download Enclosed Map: This relies on you having ‘closed’ your route (which we’ve already discussed). If you have a closed route, this option will download the maps inside it. Useful for mobile devices probably, but again not useful if you have the full UK map already loaded.
Route Waypoints Menu
The waypoints that make up a route also have a context menu associated with them. If you right click any waypoint in a route you will get this menu (see screenshot left).
Goto waypoint: Only useful if you’ve got a GPS attached, as this shows direction and distance, in two small popup windows, to this waypoint from your current position.
Offset by: Opens a settings dialog that allows you to add a value for Offset and Bearing for this waypoint.
Add waypoint before: Adds a waypoint, locked to your mouse pointer, in between the waypoint you’ve just clicked and the one prior to it. When you click on the map the new waypoint will be dropped in that position.
Add waypoint after: The most useful option in this menu. You will use this a lot, to extend or continue an existing route and to add new waypoints into the middle of a route. A new waypoint will appear, locked to your mouse pointer after the waypoint you just clicked. If you’re in the middle of a route, just one waypoint is added and you then need to click the new waypoint and either right click and select ‘Add waypoint after’ again, or hit the ‘Insert’ key, both will create a new waypoint locked to your mouse cursor.
If you clicked the last waypoint in the route and selected ‘Add waypoint after’, you won’t need to keep clicking the option, it will basically take you back into route creation mode and you can just click to add new waypoints, until you close the route using ‘Esc’, or by double clicking, or by clicking on the first waypoint in the route.
Drop waypoint: Removes the waypoint from this route, but doesn’t delete it from MM, it leaves it as an orphan beside the route.
New in v6.4.0 Split Routes: This will split the route (or routes) that this waypoint is a part of, at this waypoint. The result will be two routes, one with the original name, and one with the same name, but suffixed with ‘-split’. Similarly, the waypoint you selected to split the routes will have been duplicated, one with the original waypoint name, and one now named ‘Wpxxx-split’.
Visually it will seem as if nothing has happened. The two routes still appear to be one, but if you drag the highlighted waypoint away from its twin you will see two routes. If you right click either of these waypoints, you will now get a ‘Join Routes’ menu option where previously you had ‘Split Routes’. You can use this to join this route to another.
Joining routes takes a bit of practice, but in general ‘Join Route’ will choose the nearest joinable end of a route within 5km.
Route Properties: Opens the Overlay Properties window (if it’s not already open) for this route.
Waypoint properties: Opens the Overlay Properties window (if it’s not already open) for this waypoint.
Lock waypoint: Locks the waypoint, so it can’t be deleted. If the route is not locked and you delete the route, this waypoint will be left on the map, orphaned.
Delete waypoint: Deletes the waypoint from the route and from MM. You can also use the ‘Del’ key on the keyboard, once you have selected the waypoint. In order to complete the deletion of the waypoint MM prompts you with a traditional Windows confirmation dialog box.
When you delete a waypoint, the next numbered waypoint will be selected. This makes it easy to delete large sections of a route just by hitting the ‘Del‘ key and ‘Enter‘ key in quick succession.
However, and this is a big caveat, remember that the numbering of waypoints is not always logical (see above) and the next numbered waypoint may not always be the next waypoint in the route! As a result, this process can be a bit hit and miss. Ideally start at the earliest waypoint you want to delete and work your way forwards along the route hitting the ‘Del‘ and ‘Enter‘ keys. As you select and delete the first waypoint, the next numerical waypoint number is selected by default, so you can just hit delete again. If however, you have lots of routes in memory, there is a chance that the next waypoint that is selected after you hit delete on the first one will be in another route (or earlier in the same route) and not even on the screen. In this case, you’ll need to select each waypoint individually to delete it, otherwise you may inadvertently be deleting waypoints in another route.
Working with Tracks
Once you get used to the system you will find that:
- Tracks cannot be amended in the same way a route can
- Tracks can be joined and separated (or split) using the right click menu.
- Tracks can be converted to routes
If you want to join two routes together, the only way at the moment is to convert them both to tracks and then use the join track option, from there you can convert back to a route, which is all a bit of a pain, but does achieve the goal. I am reliably informed that joining of routes will be available shortly!
Many of these options are the same as the routes context menu already discussed. Some of the differences are as follows:
Profiles: this now offers a sub-menu and off this we have options that relate to a track that has been recorded by a GPS and imported into MM. So things like elevation as recorded by the GPS, Speed as recorded by the GPS and so on appear in here. If you’re recording device supports heart rate tracking, you can profile that in here too.
These options are no use at all if it’s a track you created manually!
Off the Operations menu
Print Track: The purpose of this option is obvious and I cover printing in a later section of this guide.
Split Track: splits the track into two separate tracks at the point you right clicked, or possibly at the nearest change in direction to that point.
Join Track: allows you to join two tracks. However, the join may not work if the two tracks are widely separated. If they are quite close together the join should work with the default MM settings.
If you try to join two tracks and nothing happens, you will need to open the Overlay Properties for one of the tracks, set its ‘Min update distance (m)‘ field to a big number and try the join again.
If this still doesn’t work, try creating a short track between the two target tracks and use this to join them together.
Convert to Route: Converts the track to a route, complete with waypoints that you can then manipulate it. As mentioned earlier, this is useful when you need to join two routes together. You will find that the default settings on the track properties will produce a route with many fewer waypoints than you would expect, with the resulting route looking very different from the source track. This can be resolved using the same setting as above, ‘Min update distance (m)‘ only this time we need to set the number as small as possible, ideally zero. Once you’ve modified this track properties setting, convert the track to a route and the route will be identical to the track. (Thanks again to Dales for this tip, see comments below).
Remove Trackpoint: is a function of a recorded track from a GPS. A trackpoint is a point in time recorded by the GPS, there will be many trackpoints recorded every minute and this allows you to remove the one closest to the mouse pointer. Useful if the GPS lost signal for a few seconds and has bounced around looking for it. You will end up with a very spiky tracklog and removing some of these trackpoints will remove the spikes.
Reduce Points: removes a percentage of the trackpoints and reduces the granularity of the recording. The more you reduce points, the smaller any resulting GPX file will be when you export it. So it’s great for sharing tracklogs, if all you want to share is the route you followed and you’re not bothered about losing detail.
Remove Velocity Spike: does a similar thing, but its more accurate to use Remove Trackpoints
GPS Demo: recreates what a tracking GPS looks like. Not very useful as it runs in real time, so a four hour walk will take fours hours to play out!
Modifying the appearance of Routes & Tracks
It’s possible to change the way Routes and Tracks appear on the map, which is useful for distinguishing between multiple tracks or routes in the same overlay, or for preparing the track or route for printing. The options for change are mainly concerned with colour, width and opacity. The Overlay Properties boxes for Tracks and Routes are shown below, along with examples of what the tracks and routes look like when you’ve had a play with their settings
Default attributes – normal width, default colours
Thick line width, line colour changed to red on the route
Extra thick line width, line colour changed to red on the route
Normal line width, dotted line style, line colour changed to blue on the track
Extra thick line width, dot-dash line style, colour changed to green
Extra thick line width, dotted line style, 75% transparency
Extra thick line width, solid line style, 50% transparency
From a personal point of view I find that tracks are visually more pleasing than routes and if I print a map with a walk on it, I tend to use tracks rather than routes. I find that the waypoints in routes get in the way when you’re looking at a printed version, and as it’s very easy to convert a route into a track, it’s a no-brainer for me.
After trial and error I’ve found that a Thick track, in Yellow, with a Transparency of 50% makes for a great printed route.
Working with Marks
Marks are very similar to waypoints, the only difference being that a waypoint is a type of Mark that is used to construct routes, and they have very little use outside of this function. Marks on the other hand are very useful indeed.
Think of Marks as a way of adding items of interest to your maps; that may be hill summits or trig points, car parking, camp sites or B&B accommodation – pretty much anything you could want to add to a map or route. I have dozens of overlays with nothing in them but Marks – my hill lists and trig point lists are just huge collections of Marks. Big lists can take a while to load into memory, and MM sits there like it’s broken while they load.
Having said that, the v6.4.0 update has significantly improved the load time for large files, so you should not encounter this issue any longer.
Adding your own icons
Although MM comes with a couple of dozen different icons for Marks, it’s also possible to add your own. You just have to follow a few simple rules.
First of all the icon must be 32×32 pixels in size and the file format needs to be one of: PNG, BMP, JPG or GIF.
To import them into MM you use the Overlay > Icons menu option and then select the [Add] button. Point to the chosen file, click [OK] a couple of times and you’re sorted. You can now use your new icon on a Mark.
If you decide you want to remove the icon later, you can use the [Remove] button. Highlight the icon you want to delete and hit [Remove]
New in v6.4.0 If, like me, you found icons becoming duplicated in your list, MM have now released a fix for this. Icons with the same name will not be allowed to duplicate in the icon list.
Working with Files (Overlays)
This is maybe the hardest concept to come to grips with when using MM. MM doesn’t use files the way every other Windows App does. You don’t open and close files in the traditional manner. For one thing, MM will not delete what’s in memory when you close the app, it stores it in a temp file for you. So when you open the app again the same routes, tracks etc. are still there. This is both a blessing and a curse!
MM uses Overlays. An Overlay is a collection of routes, tracks, marks and so on. Importing an overlay is equivalent to opening a file. Exporting (either ‘all’ or part of the resident overlay) is equivalent to saving a file.
The first thing you will try to do, is to have one overlay file with all your routes in, which is always open, problem solved right? Not really. Overlays with more than a few routes and tracks become very unwieldy. When you add a few hundred Marks into the mix as well, the situation becomes impossible. When you launch MM it will take longer and longer to open as it processes the increasingly large Overlay. Adding new Routes and Marks will become really slow, manipulating existing items will be painfully slow. Even with a very fast PC and loads of RAM using MM can be very, very time consuming when you have lots of data in the Overlay.
I’m currently running an 8th Gen Intel Core i7-8700 @ 3.2GHz with 16Gb RAM and an overlay with just the Database of British Hills (25,000 Marks) can take 2-3 minutes to load into MM.
New in v6.4.0: This major release has dramatically improved loading times of large overlays. There is almost no lag now, even on large files like the Database of British Hills. The previous 2-3 minutes load time is now just a few seconds. Having said that, the advice in the next paragraph still applies and I have found best practice is to break your overlays down into individual files where possible.
The best approach is to break your Overlays down into individual files and find an acceptable compromise between the number of items in an Overlay and the time it takes to load into MM. In the example above, I break the DoBIH list into regions (using ‘Save Enclosed Marks’) and load the region I need at the time.
When you have a group of routes created and want to save them, you use the menu option Overlay > Export All and MM prompts you for a location to save the file to. If the file already exists you get the usual Windows prompt to overwrite the file.
If you want to save a single route you can right click the route and select ‘Save As’.
As you can see from the screenshot below, if you want to save a group of routes, tracks or marks, you can create Categories within the Overlay Object panel to group items together. You can then right click the Category title and ‘Save As’ into a new Overlay file.
With dozens of routes on the screen, things can start to get messy very quickly with routes crossing all over the place. Fortunately, you can hide data so it doesn’t appear on the screen. You can hide individual routes, tracks and marks, or whole categories, or all data if needed
In the screenshot above you can see a check box beside each of the items in the Overlay. Deselect the checkbox to hide the item (or Category) from the map display. Even though it’s hidden, the data stays in the Overlay, even when you save it, but just doesn’t appear on the screen.
The menu option Overlay > Hide All.. allows you to select types of data to hide. This includes an All option which will hide all data. You can also hide all data matching a certain string, for example, hide anything beginning with ‘Dales’.
A useful feature is the ability to hide a bunch of items then only save the ones that are left visible. Use the menu option Overlay > Export Visible, to do this. You will only be saving what you see on the screen. Often useful for just saving a couple of routes in one overlay file.
You can also choose to Delete all the data that is hidden, using the Overlay > Delete Hidden option.
Important Note: If you save overlays as GPX files (see below) it is worth noting that there is no facility in the GPX file format to store the visibility flag of an item in MM. This means that you can set routes, tracks or marks as ‘Hidden’ in MM, but if you save as GPX, when you subsequently come to import that file again, all hidden items will be visible again. You will need to Save As.. MMO format to preserve the visibility flag.
MM uses two main file formats.
- MMO files are their own proprietary ‘Memory Map Overlay’ files and are only usable in MM. No other mapping tool can use this file format.
- GPX files are ‘GPS eXchange Format’ files and as their name suggests are designed to be exchanged between systems. If you want to use your data in an external system, you need to save as GPX
It is important to remember that MM v6 introduced a new version of MMO file, which is not backwardly compatible with MM v5. This means, if you want to use data from v6 in v5, then you must use GPX file formats. MMO files saved in v5 can be opened in v6 however, just remember not to save them if you want to open them again in v5.
MM v6 also made another big change and that is the default file format is now GPX rather than MMO (for update, see below). This change was supported by an increased level of detail that is saved as part of the GPX file. For example, a GPX file exported from MM v5 didn’t save your style changes to tracks (thickness, colour, etc.) so when you imported them, they all took the default track style, even if you’d modified them. The new v6 GPX format has new sections for style information, so these will now be retained when you export and then import them. This means they act much more like an MMO file and makes the transition to GPX much easier.
Important Note: Although GPX is the new default format I would still recommend saving your overlays as MMO files, unless you are transferring the information to another system or device. The fact is that GPX just doesn’t store all the information you may need. I mentioned earlier the loss of the ‘visibility’ flag, but this applies to other things too. For example, if you use text boxes to annotate your data, these will not be saved in the GPX file. If you come to restore from GPX later, all your text boxes will be lost. (I discovered this after being contacted by someone who had encountered this exact problem!)
New in v6.4.0: This release of the product makes saving and importing a little easier. The Save As and Overlay Import options, will now remember the file format you chose. So if you always prefer to save and import in MMO you won’t have to keep changing back from GPX all the time. A huge time saver!
I’m no expert, but I’m assuming that when these are imported into third party products that read GPX files, these sections are ignored by that program if they don’t recognise them, because they don’t fail to import. MM v6 GPX files use the v1.1 Schema that supports personalisation to an extent, provided it follows the correct format, so I’m assuming that the MM have implemented their own ‘extensionsType’.
The third file format that may be of use is CSV, or ‘Comma Separated Values’. Like GPX, this is a plain text file format but unlike GPX, a CSV file can be read and manipulated in apps like Microsoft Excel. We cover the use of CSV files in a lot more detail later in this guide.
MM can also save out to a couple of other file formats; ESRI Shape files (SHP) and Geocaching (LOC) files. I’m sure these will be useful to someone, but I’ve never had cause to use them.