This is a FUSION Firearms, 357 SIG, 5 Inch Standard Government Length ”Drop in" 1911 416 stainless steel PRO-Series Match barrel with matching stainless steel bushing for a 1911 model colt style pistols and Clones.This barrel will work with all 40 Cal and 10mm slide breech faces. So it is an easy painless conversion to the 400 Corbon from 40 or 10mm. These Barrels are some of the best for accuracy and function on the market today. It will improve accuracy with any brand of 1911, dramatically. Work to its best ability when used with our Drop-in match barrel bushing. These parts are made to complement each other. Fusion, Made entirely in the USA on some of the highest grade barrel making equipment available. These are some of the best barrels on the market today. Being match grade some slight fitting may be required. Buy with confidence.. Buy FUSION Parts.