The Streamlight ProTac Rail Mount HL-X is a 1,000 lumen weapon-mounted light featuring a dedicated fixed-mount for Picatinny rails. It uses either a remote switch with momentary or constant on operation or a standard push-button tail switch, and runs on either two CR123A lithium batteries or one Streamlight rechargeable SL-B26 (18650) battery. This light can be attached easily with the fixed rail grabber with thumbscrew so no tools are required. Lightweight, this bright light can be used in close quarter compact or to identify medium range threats. Its easy to use pressure switch comes with a button for on/off and a pressure switch for momentary activation. Ten-Tap programming provides operators with custom options.