A friend of mine is giving me his Garmin GPS device to update the maps for him but he doesn't know which model it is. He got it from another person and never learned the model in the first place. Is there a way for me to see the device model somewhere - either on the device or in some file? Thanks.

Every Garmin device has in settings menu a point system-info or similarly with device name, software versions and some other informations.

And there is always a file GarminDevice.xml in folder Garmin. There you find under <Model> <description> device name and other infos.