This is a new Fusion Mil Spec grade Carbon Steel Standard Flange (.090”), Small ID, barrel bushing for older 9mm colt style 1911 pistols with the .500" ID bore. Full size 1911 pistol. Drop in style, All Machined in the USA on state of the art CNC turning centers. These are for old style "thin" 9mm barrels. All machined from pre-hardened Bar stock, so Absolutely No warpage or distortion from after machining heat-treat processes. Black Oxide finished. All made in the USA.