The AMP 1L with Bottle Opener & Cone Blue from Princeton Tec can hang off of a gear loop on your pack. Waterproof to 100M (330ft), Amp 1 LED is also at home in the worst weather. An easy to use twist bezel activates the light and keeps it from turning on accidentally in transit. It comes with a snap on cone to convert your flashlight into a marker light just in case.