Give your Glock 37 new life and new accuracy by replacing the original .45 GAP chambering with this .40 S&W Conversion. The replacement barrel is precision-engineered from 416 stainless steel for flawless performance. Easy drop-in fit, no gunsmithing required. Made in the USA. Converts your G37 from .45 GAP to .40 S&W Match-grade barrel is crafted from precision-engineered, CNC-cut 416R stainless steel 1:10" right hand twist Drop-in fit, no gunsmithing required Compatible with lead bullets Made in the USA Backed by a Manufacturer's Limited Lifetime Warranty Includes barrel, extractor, and magazine follower Order today!