Silencerco’s threaded barrels for Glock® handguns are made from 416R stainless steel and available with a black nitride or natural stainless steel finish. These fit both Gen 3 and Gen 4 Glocks®. 9mm barrels have 1/2x28 threads, while the .45 ACP barrel has .578x28. Includes thread protector.
Big Book Catalog, Issue:73, Page:222