This 7″ Modular Float Rail (MFR) mounts to a free-float barrel nut (not included) and gives any M4 platform the RIS picatinny/weaver rails for mounting accessories such as lights, lasers, grips, launchers, and more. Designed for installation on rifles without a front triangle sight and perfectly fits a rail mounted 203 underbarrel launcher. Constructed from durable and lightweight aluminum, give your airsoft rifle a stand-out unique look with this 7″ rail system!