The single port muzzle brake is compatible with all SilencerCo ASR Mounts. It offers quick and easy one-hand-on, one-hand-off attachment and detachment. The 1-port design effectively reduces felt recoil and muzzle climb. Each ASR muzzle brake comes with a shim set and rocksett for easy application.Specifications and Features:Type: Muzzle BrakeModel: ASRSize: 7.62x39mmMaterial: SteelThread Pattern: 5/8"-24Finish: Black