Anarchy Outdoors HK VP9 SK Compensator Red. The compensator attaches to the muzzle allowing the gasses to combat recoil without sacrificing shot power. It helps you get back on target for a quicker follow-up shot. This product is not manufactured authorized endorsed or warranted by Heckler & Koch. Specifications for Anarchy Outdoors HK VP40/VP9/VP9 SK Compensator: Manufacturer: Anarchy Outdoors Caliber: 9mm Luger Gun Make: Heckler & Koch Features of Anarchy Outdoors HK VP40/VP9/VP9 SK Compensator Reduces kickback by up to 50percent by pushing down the muzzle and redistributing gas pressure; Does not sacrifice shot power; Helps reduce the time between shots; Easy installation Package Contents: Anarchy Outdoors HK VP40/VP9/VP9 SK Compensator What firearm models does the manufacturer say Anarchy Outdoors HK VP40/VP9/VP9 SK Compensator is compatible with? The manufacturer says that Anarchy Outdoors HK VP40/VP9/VP9 SK Compensator is compatible with Heckler & Koch VP9 SK Heckler & Koch VP9 Heckler & Koch VP40Anarchy Outdoors 791617487017: HK VP9 SK Compensator Red