ALL NFA RULES APPLY. Resistance silencers are user serviceable ensuring long, high performance service life. The front caps can be interchanged on the Resistance 9 & 45 models for the smaller, .22 caliber or 9mm front caps. 17-4 stainless steel, heat treated, patent pending, ECO-FLOW baffles, with anti-rotation features, ensure maximum strength and sound performance as well as reduced gas blow back on semi-auto or full-auto firearms vs traditional designs. Included take down tools allow for an easy and satisfying end user maintenance experience. Numerous mounting options are available : CAM-LOK QD pistons and associated CAM-LOK adapters Integral Low-Profile 3 lug adapter kit and associated 3-Lug barrel adapters and 45cal 3-Lug barrel adapters. Taper Mounts via the Taper Mount minimalist blast shield, Taper mount PLAN-A, and fixed direct thread mounts A2 Blast Shield Fixed Barrel Spacer What's in the box? Silencer tube body ECO-FLOW baffle assembly 45cal front cap Boost assembly (retainer, spring, o-ring & housing) Piston not included (compatible with EZ-LOK , CAM-LOK , & Traditional Pistons) Multi-Function wrench Front Cap tool Branded Griffin pouch Manual