Directs muzzle blast forward on short barrel rifles and pistols. Does not reduce recoil or flash. Constructed from 6061 aluminum, and hardcoat anodized for a lifetime of service 1/2-36 threads for 9mm AR type pistols and rifles with 1/2-36 barrels Includes new crush washer Overall length 3.375 Outside diameter 1.2 Weight 3.2 oz 100% made in the U.S.A. Note: Will not work with barrels that do not have 1/2-36 threads Mfg: Midwest Industries, Inc.