Storm Lake barrels are machined from solid 416 stainless barstock, tolerances held to +/- .001" in critical areas, finish heat treated to 40-42 HRC and cut broach rifled. Barrels feature left hand 1 in 16" twist with 6 lands and grooves. Barrel kits are drop in and usually require little to no fitting. The barrel link, barrel link pin and barrel bushing are included and have already been fitted to the barrel, making this an easy upgrade to the accuracy of your favorite 1911. Storm Lake requests that they be contact first regarding any issues with a Storm Lake product.