The AR-STONER(TM) 9mm Magazine Adapter Block for the AR-15 platform converts your standard lower to accept 9mm rounds. The anodized aluminum, 9mm mag block with steel insert for feed ramp, accepts Colt style 9mm magazines. Installation is quick and easy. Use a 1/16 and a 5/64 (not included) hex key on the the provided screws to lock down and secure this mag block. Building a pistol-caliber carbine or extending your day at the range is now easier and more cost effective with the addition of the AR-STONER(TM) 9mm Magazine Adapter Block. NOTE: 1/16 & 5/64 Hex key are not included Installation DirectionsRemove retaining screw & washer combo using 5/64 hex keyInsert mag block into lower receiverInstall retaining screw & washer comboInstall set screws (x2) with the 1/16 hex keyFeaturesEasily Converts Standard AR-15 LowersAccepts Colt Style 9mm MagazinesAnodized Aluminum ConstructionSteel Insert for Feed RampQuick & Easy Installation