NovaTac Special OPS LED Flashlight 3 Pre-set brightness levels for maximum versatility (0.3, 30 or 120 Max Lumens) Disorienting strobe and momentary maximum mode can be used as safety/signal feature Flat Button prevents accidental turn-on Powered by (2) CR123 batteries (included) Runtimes: 120 lumens/70 min., 30 lumens/9 hrs., 0.3 lumens /500 hrs. Measures 4.6 inches long by 1 inch wide and weighs a mere 3.9 oz.