What sets the M4 RAS other than other two-piece quad rails out there is the fact that it securely locks on the rifle’s barrel nut through a clamp and screw arrangement, making it an exceedingly stable Basis on which to mount tactical components. Involves 3 KAC 11 Rib Rail Panels. https://kacrail53962.thekatyblog.com/26160227/the-fact-about-knights-armament-rail-that-no-one-is-suggesting