The CRB provides competition, duty and recreational shooters an increased ability for faster sequential shot placement. The unique off axis forward slanted ports of the CRB destroys felt recoil and muzzle rise.Function of the CRB muzzle device is only equaled by the exceptional visible manufactured quality and apprearence you expect from Cross Machine Tool products. PROUDLY MADE IN USAFEATURES-     Manufactured from  Stainless Steel.    Standard-QPQ Nitride finished for durability & corrsion protection-standard.     5/8-24 RH ID threads    Surface Hardness-68RC    Weight- 3.7oz     Caliber- up to .30 caliber.    Max O.D.- .990"    Diameter that meets barrel- .872"    OAL- 2.560"    Rating- Full Auto    Zero porting on bottom side to reduce ground signature when fired from the prone position.   3 forward angled, off axis progressive side exhaust chambers.   Crush washer included, shims may also be used.   Made in the USA