Kexuan AR-10 / AR-15 Steel Competition Grade Muzzle Brake Recoil Compensator. Steel competition-grade muzzle brake for AR-10 LR 308 and AR-15 .223, with 5/8x24 and 1/2x28 threads. Includes jam nut and crush washer. Redirects propellant gases to counter recoil and barrel rise. CNC machined steel construction. Package contents: Muzzle Brake Recoil Compensator, Jam nut, Crush washer. Compatible with AR-10 LR 308 and AR-15.