The Garmin Rhino is the gear ,5 watt radio , can be mated with others so you can see where your mates are ,that is on the map so it is distance and direction, and can text silently.
One thing Waidmannshiel did not mention is that they are pretty damn tuff.
The battery lasts for days on 1 charge ,and you you can get a carrier to take the disposable dry cell type battery