Protac Railmount Hl XThe Streamlight 88066 ProTac Rail Mount HL X is a 1,000 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 18650 battery.