Larry Williamson’s everydaycarry.com pocket dump is fairly comprehensive, including as it does a Whistles for Life Tri-Power Safety Whistle for Scuba Divers and Snorkelers. In fact, I can’t think of what the “technician’s” everyday loadout doesn’t have. Wait. Yes. Coffee. It doesn’t even have Coke Zero! (Sponsored by Instructor Zero.) What do you think his backpack lacks?