Aero Precision, Delta 556, Muzzle Brake, 223 Rem/556NATO, Bead Blasted Stainless Steel, 1/2X28 The Delta 556 contains no chambers so gas is expelled more forward which reduces the concussion to the shooter although recoil mitigation will feel similar to that of an A2 birdcage. This is a great all around device for tactical, competition or recreational shooters at a very affordable price.