Underwater Kinetics 3AA eLED CPO Tail Switch5 1 4" overall. Black high impact ABS construction. White LED. 110 lumens. Runtime: up to 8h. Visibility: up to 304ft. Water resistant: up to 10ft. Features Thermal Recovery System that transfers heat from the LED to warm batteries for better cold weather performance. Waterproof. O ringed sealed. Compound Path Optics (CPO) permits high efficiency and compact size. Push button tail cap switch. Uses three AA batteries (included). Can be mounted to any