The Area 419 Fixed Barricade was developed for use on the flat ARCALOCK rails such as the 12a ^2 Universal, M-LOK, Keymod, and MPA that do not have a built in stop. The barricade stop slides on from the end of the rail and can be locked in any position on the rail. It uses a pinch clamp design and also a set screw to engage one of the ARCALOCK cuts to guarantee no slippage. A 3/32 Wrench included and required to move clamp, not designed to be a moveable stop. Grooved surface to aid in gripping the barricade.