Polymer80 Glock 17 Standard DLC 9mm Barrel, Black. This drop-in, Match-Grade barrel for Glock 17 pistols is CNC machined from 17-4 PH stainless steel bar stock and heat treated to 42 HRC. This barrel is broach cut rifled and features a black Diamond-Like Carbon PVD finish. After final finishing, these barrels go through multiple inspections to ensure an accurate, high quality barrel. This barrel will work with Glock G17 Gen1-4 pistols, and Polymer80 PF-Series compact frame 9mm pistols.The P80 line of G17-compatible barrels are precision CNC machined to exacting tolerances from domestically-sourced 17-4 PH stainless steel bar stock. After comprehensive inspection, the barrels are then cut broach rifled and vacuum heat treated to 42 HRC. Following final finishing and coating (optional), they are subjected to multiple inspections to ensure that you receive the highest quality and most accurate barrel in its class.Structural aerospace grade 17-4 PH stainless steel allows for a simple, single-process heat treatment for virtually no loss of dimensional accuracy and maintains the high strength and optimal hardness of the barrel throughout rigorous strings of fire and high operating temperatures. The available Titanium Nitride and DLC (Diamond-Like Carbon) PVD finishes offer upgraded aesthetics, high dry lubricity for enhanced smoothness during cycling, and ease of cleaning.