[rrugps]

I need to purchase some GPS units to perform the following functions following a natural disaster such as hurricane, tornado etc.

1. Be able to navigate the streets in an urban area with voice prompting
2. Be able to use as a handheld GPS unit while doing inspections on foot
3. Need a clear display in sunny conditions as well as night time
4. Long battery life (at least 16 hours and must use swappable AA batteries)
5. Water resistant
6. Need belt clip/holster


I realize these are somewhat sketchy requirements, but I'd appreciate your help as we need to urgently purchase these devices for our deployable teams.
Thanks!