The "I can't be out of touch" reason for not going on a river trip is no longer valid. An Iridium phone is not only for emergency, you can also check in regularly on how things are out in the world back home or in the office. The 9505A phone is larger than a typical mobile phone, but still small enough to carry in a backpack. It is very simple to use, water,shock & dust resistant and lasts up to 30 hours of standby time - 3.2 hours of talk time. Weight 13.2oz.