Safariland Model 6004-22L Quick Locking Receiver Plate with Locking Feature, Single Kit Only, Black Finish 6004-22L-2 This QLS 22L Quick attachment holster system receiver plate with lock is for the mounting platform for the QLS locking fork. You can mount your holster nearly anywhere: belt, thigh rig, in the home or even in a vehicle. It works with nearly all Safariland holsters and duty gear.