This modular suppressor features full-size and K configurations, multiple mounting options, and lightweight construction for versatile performance. It s full-auto rated for .45 ACP and includes a piston, booster assembly, and thread protector. Full-Auto Rated The FLOW 45 M is full-auto rated for a magazine-fed .45 ACP platform. What's Included: Suppressor Suppressor Module External Thread Protector .578-28 Piston and Booster Assembly Wrench