The Surefire UE tail-cap is compatible with any Surefire Scout M300 or M600 light, plus the Arisaka 300 and 600 series lights and light bodies. It is designed to work with the Surefire remote switches, including the SR07 and ST07. This product is for the socketed tail cap only and does not include a remote switch. The UE is MIL-A-8625 Type III hard coat anodized.