CMC's Match Precision Barrel is constructed of pre-hardened 416R premium grade stainless steel with 6 grooves and is rifled cut. The drop-in barrel is fluted, bead blasted for a satin finish, and has a SAAMI match grade chamber. This model is compatible with Glock 19 Gen 3 & 4 models, has a black DLC finish with hBN (Hexagonal Boron Nitride) bore and chamber. It is threaded with 1/2x28 tpi threads.