Slide Fire Recoil Enhancers are a black anodized barrel attachment. This attachment increases the maximum amount of recoil without adding any unnecessary weight. All of the ports are specially engineered to increase the felt recoil. The increase in recoil helps the S&W M&P 15-22 increase its firing reliability. This attachment is designed to fit on barrels with 0.5 inch - 28 tpi threaded barrels and the fluted design gives you a cool, unique look.