Glock Generation: Gen 3-5; An ultra-precise barrel with enhanced slide fit & lock up for improved accuracy.; Our barrels are 6 groove, cut rifled, 1:10 Twist Right Hand, fully QC inspected, double honed (rough and finish) to produce the smoothest bore possible; Max Roughness Average (RA) of 12; Finished bore dimensions are held to +/- 0.0005" tolerance from nominal groove and bore dimensions but the dimensions are uniform to within 0.0002 for maximum consistency, accuracy and quality; Barrels are bead blasted to create a satin finish prior to plating; Finish:Black DLC, with ultra low friction hBN (Hexagonal Boron Nitride) Bore & Chamber; Does not require gunsmith assembly; Affordable, ultra accurate, durable upgrade to your existing Glock(R) 17,19 or 34 factory barrel; Straight fluted for aesthetic purposes