This is our newest rear stock design with folding adapter for MASTER PIECE ARMS .45 ACP guns. It offers a solid stock design and with the folding adapter & weighs just over 1.4 lb. with the folding adapter. It measures about 9.25" from the rear of the receiver. Finished in jet black anodize bolts up to the rear using existing threaded hole, button head bolt and Allen wrench & instructions included. Folding adapter can be switched to fold to the left or to the right. Fits Master Piece Arms .45 acp only. (gun & other parts sold separately)**TELL US IN THE COMMENTS SECTION OF YOUR ORDER IF YOU HAVE AN OPEN BOLT MAC-10, WE NEED TO GIVE YOU A DIFFERENT BOLT AND INNER THREADED BLOCK.