This muzzle device will allow a shooter to utilize any of the R556, R556A1, R556A2, R30A1, or R30A2 suppressors on weapons that have 1/2×28 muzzle threads. Featuring 5 ports, a taper mounting surface, and a ratcheting secondary retention system, this 5-port muzzle device will ensure precise and repeatable performance from your suppressor. Constructed of heat-treated Chomoly Steel with OXyN gas nitride finish.