From the manufacturer Streamlight 8866 ProTac Rail Mount HL-X Dual Fuel Long Gun Light Lightweight, compact, low profile, and high lumen The Streamlight 8866 ProTac Rail Mount HL-X is a 1, -lumen weapon-mounted light featuring a rail clamp designed to rapidly and securely attach/detach from rifles, carbines, and submachine guns with a MIL Standard 1913 Rail. It uses either a remote switch with momentary/constant on operation or a standard push-button tail switch, and can run on either two CR123A lithium batteries or one Streamlight rechargeable 1865 battery. Product Dimensions: 5. 43-Inch length; 1. 45-inch width; 1. 72-inch height. Product Weight: 6. 4-Ounces with CR123A batteries (included); 6. 9-ounces with optional 1865 Li Ion rechargeable battery (sold separately). TEN-TAP Programming with Three User Selectable Programs: Tail Switch & Remote Switch: Standard push button tail switch and remote switch with momentary/constant on operation. Dual Fuel Technology: High for maximum illumination: 1-lumen; 27, 6-candela; 332-meter beam; runs 1. 25-hours (CR123A batteries) or 1. 5-hours (1865 battery). Low for extended run time: 6-lumen; 16-candela; 8-meter beam; runs 2-hours (CR123A batteries) or 22-hours (1865 battery). Strobe for signaling or disorienting: runs 2. 5-hours (CR123A batteries) or 3. 25-hours (1865 battery). Additional Features: Light Source: LED technology, impervious to shock with a 5-hour lifetime. Solid state power regulation provides maximum light output throughout battery life; reflector produces a concentrated beam with optimum peripheral illumination. Built to Last: Durable, 6 Series machined aircraft aluminum construction with impact-resistant tempered glass lens. IPX7 waterproof to 1-meter for 3-minutes (with tail button switch); IPX4 water-resistant (with remote switch). Mounting: Fixed rail grabber with thumbscrew easily attaches to Picatinny rails (no tools required). One handed snap-on & tighten interface keeps hands away from muzzle when attaching/detaching. Why Heroes Trust Streamlight: It all comes down to performance. Period. People who depend on their flashlights, often for their lives, need to be able to count on that flashlight to work. Every time. When it’s freezing cold, scorching hot, desert dry, or rainforest humid. When it’s been beat up, abused, dropped in water, or left in icy snow. They need to know that their flashlight will deliver the light they need for the task at hand. Whether it’s lighting up a whole room, throwing a beam way down a path or up to the sky, or reading a map without being seen. When size and run time are also part of the performance, people know they can trust Streamlight to shine brighter, work better, and last longer. The Streamlight 8866 ProTac Rail Mount HL-X is a 1, -lumen weapon-mounted light featuring a rail clamp designed to rapidly and securely attach/detach from rifles, carbines, and submachine guns with a MIL Standard 1913 Rail. It uses either a remote switch with momentary/constant on operation or a standard push-button tail switch, and can run on either two CR123A lithium batteries or one Streamlight rechargeable 1865 battery.