The Streamlight ProTac 2.0 Rail Mount is a high-performance 2,000-lumen weapon light powered by the proprietary SL-B50 rechargeable Li-Ion battery. The battery features an integrated USB-C port and is keyed for perfect alignment. It offers three user-selectable programs and versatile activation via a tactical tail cap or remote pressure switch. Black Anodized Aluminum construction, ambidextrous, OAL 6.30, Head Diameter 1.46, Body Diameter 1.02, Weight 9.06 oz, IP67 Waterproof and Dust Proof, modes Constant / Momentary / Strobe. Includes SL-B50 battery, USB-C cord, remote switch, and mounting hardware. Provides 2.5 hours of runtime on High and 11 hours on Low.