This is one of the things we'll throw in our pack when we're doing a big adventure ride, especially when we know there isn't good (or any) cell phone reception. It's great because you can send and receive messages through the device using satellites so you can keep people updated on your status even if it isn't an emergency. And if it is an emergency, it connects you with a dispatch service so they can get you evacuated as quickly as possible - something we haven't had to use yet and we'd like to keep it that way!