The Griffin Armament 30SD muzzle devices interface with our 30SD and M4SD series of silencers as well as the QD Blast Shield. - 30SD muzzle devices provide high performance mounting option for Griffin QD Silencers as well as a 30 caliber interface for the QD Blast Shield. The Flash Comp Flash Suppressor and Muzzle Brake were made with the same performance features as their 5.56mm counterparts but with a 5/8x24 threaded interface and integral overtravel stops. An additional pin is pre-fit for pin and weld applications. The gunsmith only needs to screw the muzzle device on and press the rear pin flush for pinning and welding. The 30SD Muzzle Brake is included with the 30SD silencer. CNC Machined and outside diameter ground from high strength corrosion and wear resistant 17-4 precipitation hardened stainless steel the 30SD muzzle brake is black oxide finished. 5/8x24 threads offer compatibility with most 7.62mm firearms on the market. - Includes shim set. - Diameter: .863 - OAL: 2.770