The Pelican™ tactical flashlight runs on 1 AA battery, or upgrade to 1 CR123 battery to bring you up to 445 lumens of bright LED light. It has high, medium, low and strobe beam light output modes, 4 programmable modes, 5 selectable programs and a full-time battery indicator, making this the most efficient and practical tactical light you will ever own. Its push button / momentary button makes it a convenient light source that will run up to 13 hours on the low beam setting with CR123 battery. The Type III Anodized aluminum body, IPX8 (1m) rated lens and carbon steel clip make it durable and convenient to carry. Includes 1 AA battery and Pelican's unconditional lifetime guarantee of excellence.