Presma Steel Muzzle Brake fits 1/2x28 Free Crush Washer & Jam Nut, for 223/5.56

One piece high quality steel construction with CNC machined Easy install/release, free crush washer and jam nut Recoil/pressure/rise reduce for better performance Truly tactic competition grade Dimension: 0.9*1.3*2.7 in, 6.7 oz Fit .223/5.56, Thread 1/2"X28 Brand SNIPER Model ASMZ20 MPN ASMZ20 UPC 00840354115674 .