GG&G, Inc. Black, Matte GGG-2719M The GG&G Beretta Stock Adapter is easy to install as long as you have a working knowledge of stock removal procedures. No modification to the shotgun required. GG&G offers two different Beretta 1301 Adapter Kits" A Magpul Mossberg Stock Adapter that allows you to install the Magpul SGA Mossberg 500/590/590A1 stock to your Beretta 1301" and a Magpul Remington Stock Adapter to install the Magpul SGA Remington 870 Stock. Both Beretta Adapter Kits include installation hardware" an ergonomically designed adapter that mates with the receiver and the stock and the all important Spring Tensioned Bolt Recoil Buffer.