The SureFire RM45 off-set mount, is designed specifically for Scout Light models it is equipped with a thumbscrew clamp. It positions the light in the off-set position between the rails of a MIL-STD-1913 (Picatinny) forend, decreasing overall weapon profile and limiting potential snag factor. The body is constructed of lightweight but strong aerospace aluminum that's hard anodized with a Mil-Spec Type III finish so it's extremely durable and resists corrosion while adding very little weight to your weapon. NOTE: This rail mount fits M300, M300V, M600U, M600V, M600P, M600AA scout lights.