Extremely Bright, Visible Beam at Night Range up to 5 Miles. Water Proof & Shock Resistant. Ruggedized & Field Tested. Choice of Modular Pouch. Includes Constant On/Off Switch with Lanyard Loop, 2 pcs CR123A Lithium Batteries. Six (6) Hour Continuous On Operation. Attach to any Standard 1" Tactical Light Mount. Combat Tested and Approved by US Army and Marine Corps units in Iraq and Afghanistan for Visual and Non-Verbal Communication, Command & Control. 50,000 units shipped since 2006.