B&T 2-chamber M.A.R.S. Compensator 1/2"-28 UNEF cal. .223 Rem is a high-quality steel (QPQ nitrided finish) muzzle brake-compensator dedicated to AR-15/M4 rifles and similar with 1/2"-28 UNEF threading. It effectively reduces recoil and muzzle rise by precisely redirecting gases to the sides, improving weapon control during dynamic shooting, and the QD system allows for quick attachment of compatible devices and silencers from the M.A.R.S. series without tools. It weighs about 140 g.