Re: Flashlight for multiple day backpack hunt???
About 2.8 ounces for Surefire Backup with the battery, About 2.3 ounces for Nitecore Tactical R2 with battery. These are small, bright, palm of your hand sized lights. They are tough too. They arent dive lights but I have never had issues with them getting dunked in water or rained on or condensation in the housings and temperatures from -40 up to 90 degrees in my own experiences. And they are all aluminum. Just solid little lights.
Nitecore also makes a headband that almost any small hand light can attach to so you can have your handheld/headlamp in one.
I never heard of underwater kinetics, I'll check those out.