SureFire SRxx Tape switch
The SRxx Rail Mount Tape Switch is a plug-in tape switch with rail clip that fits the Scout Light, Millennium Universal Weaponlights (or any XM dual tailcap), and the X200 Tape Switch tailcap. The ‘xx’ stands for the length of the cable and plug – the 7″ SR07 is shown below. The SRxx consists of an XM-type metal plug that plugs into the socket in the flashlight tailcap, a length of cable, and the rail clip with switches. The rail clip is made of flexible material and snaps onto any 1913 rail. I think the compound could be hardened up a bit so it’s a bit more secure on the rail.