The MRE package is created to work with M4 carbines, and accommodates a hard and fast A2 entrance sight tower with carbine size gas method. It extends earlier the front sight foundation, offering more rail Place for that mounting of tactical equipment. Consists of 3 KAC 11 Rib Rail Panels. https://lukasoxcko.topbloghub.com/32862423/knights-armament-m4-quad-rail-things-to-know-before-you-buy