A3 Industries HK MP5-22LR Rear Stock Adapter Picatinny 1913 Mount. Completely unique in design this adapter provides improved stability by covering more surface area of the receiver. The A3 Industries adapter allows the use of A3 Industries's complete line of modular stocks and braces and can also be configured with a Picatinny rail. The Picatinny rail will allow you to adapt any side folding stock (or arm brace) designed for use with Picatinny style mounts. The bolt pattern and locating lug on the rear of the adapter provides a positive modular mounting platform for a wide variety of currently available stocks/braces. Specifications for A3 Industries HK MP5-22LR - Rear Stock Adapter: Manufacturer: A3 Industries Condition: New Color: Black Gun Make: Heckler & Koch Gun Model: Heckler & Koch MP5 .22LR Fabric/Material: 6061-T6 Aluminum Attachment Type: Picatinny Fit: HK MP5 22LR Mount Type: Picatinny Features of A3 Industries HK MP5-22LR - Rear Stock Adapter Polymer/Aluminum hybrid design OE-fit to receiver with reinforced hinge mount No modifications to firearm needed Modular design for various cross-platform use Large #10 threads and positive lug for increased mount stability Package Contents: A3 Industries HK MP5-22LR - Rear Stock Adapter What firearm models does the manufacturer say A3 Industries HK MP5-22LR - Rear Stock Adapter is compatible with? The manufacturer says that A3 Industries HK MP5-22LR - Rear Stock Adapter is compatible with Heckler & Koch MP5 .22LRA3 Industries RSA027: HK MP5-22LR Rear Stock Adapter Picatinny 1913 Mount