Mission First Tactical Tekko Metal AR Carbine Integrated Rail System, Replaces Factory Handguard, 7 Drop In Integrated Rail System, Black TMARCIRS The Tekko Metal AR15 Carbine Rail System replaces the plastic factory handguard in minutes and requires no gunsmithing or special installation tools. Drop in" screw less" installation means no permanent alterations need be made to the rifle. The unit is held in place by the Delta ring and handguard cap. Four MIL-STD Picatinny Rails provide secure mounting for rail attachments and accessories such as vertical grips" lights" lasers" bipods and other rail mounted kit. Monolithic style continuous top rail eliminates the gap between the receiver and rail. Four QD mounts" two on each side for push button sling swivels.