Clamping block for 15 mm rails. Clamping block for 15 mm rails. This clamping block can be mounted to the rear of several base plates (USBP's (not MK II) and FS7 shoulder base plate 0350-1600) to offer a rear 15 mm solution. Besides, this clamping block can be attached to several top cheese plates and top handgrips offer a top 15 mm rails solution.
