9mm AR-15 Mag Well Adaptor for Colt style magazines. This USA Made adapter allows for easy conversion from any standard .223/5.56 lower receiver to 9mm. The easy drop in design installs in minutes, with no gunsmithing or permanent modifications needed to the lower receiver. Key features are: Last round bolt hold open Steel feed ramps Installs from the bottom of the magwell with top and bottom locking Screws/li> No dissassembly of the bolt catch required Fits Colt SMG and Uzi Style Mags T-6061 black anodized aluminum body Steel feed ramp and ejector Net weight: 4.3 ozInstallation: Remove screw and washer that is pre-installed next to the ejector Feed the magwell like a regular magazine into the mag well After locking into the lower, re-install the washer and screw Then use the provided Screws(2) and hex key to set the block into place from the bottom