Cryptic Coatings coated 9mm bolts are designed to provide reduced friction, lower operating temperatures and increased overall performance and bolt life. Our bolts are back by our lifetime warranty. Should our 9mm PCC bolts fail to function properly, return it for a brand new replacement. Our coated bolts will increase lubricity and wear resistance while providing a smoother recoil, improved accuracy, faster cyclic rates and reduce carbon fouling.