The Worlds First 5-Rail System for MP5. Compliant with MIL-STD 1913, this exceptional design allows you to fit numerous mission-specific accessories such as forearm grip, bipod, flashlight and others, on any of the 5 Picatinny/Weaver Rails. Specifically designed and manufactured to give a 100% secure fit that does not restrict barrel movement.??Constructed of billet aviation grade aluminum using CNC machinery??Easy to fit. No Gunsmithing required. Accompanied by 6 Short heat-resistant rail covers.