The VICTRA-12 Mount Assembly is a bit different than your ordinary mount assembly. Ours threads into the end of your shotgun’s barrel using the standard choke threads to mount the suppressor to the shotgun but it does not choke your shot. That is handled by our unique front-installed choke. Each mount is shotgun-manufacturer specific and we offer a multitude of mounts that function with most popular shotguns. – MADE IN U.S.A. – BERETTA OPTIMA HP MOUNT ASSEMBLY – Length: 3.681 – Diameter: 1.20 – Material: 17-4 Stainless Steel – Finish: Melonite