This set of handguards comes fully equipped with numerous Picatinny rail interfaces on all four sides, making it easy to mount any of the numerous optics and accessories available to your AR-15 in seconds. Installation requires only replacing the old handguards with these lightweight aluminum units; the original factory delta ring and handguard cap may be retained. No gunsmithing or permanent alterations are required. The bottom rail is removable in order to mount additional accessories to barrels equipped with an M203 relief cut.