The A3 Industries Skelestocks are fixed length skeleton stocks machined completely from 6061 aluminum. They are available in two lengths: 9.50in and 11.00in. They are also available with 2 different hinge options. The hinges fold right or left depending on how you mount the hinge. See hinge details below. Each stock comes with a 1/2in polymer cheek rest, 90 durometer Neoprene buttpad, and one steel, full rotation QD lug that can attach in 2 different locations on the right or left of the stock. Approved/Tested applications: CZ BREN 2 CZ SCORPION B&T APC9/45 and APC223/300 B&T GHM HK MP5 and MP5K SIG MPX/MCX (use Picatinny) RUGER PC CHARGER (use Picatinny) GALIL ACE MOST FIREARMS WITH A REAR PICATINNY RAIL NOTE: There are 2 hinges available for the Skelestock - Standard 2-bolt hinge and the A3T Picatinny hinge. Please review the details below to select the correct hinge for your application: Standard A3T 2-bolt hinge - This hinge is designed to attach to our various firearm adapters. This is used if you do not have a rear Picatinny rail. You will need one of our various firearm adapters to attach the Skelestock to your weapon. Standard A3T Picatinny hinge - Our Picatinny hinge works for all applications with at least 3 Picatinny slots. Specifications for A3 Industries Skelestock Skeleton Stock: Manufacturer: A3 Industries Color: Black Stock/Brace Material: 6061-T6 Aluminum Gun Model: Universal Gun Type: Carbine Additional Features: A3T Picatinny Hinge Gun Make: Universal Hand: Ambidextrous Condition: New Features of A3 Industries Skelestock Skeleton Stock 9.50-11in from mounting face to back of buttpad Folds left or right depending on how hinge is mounted A3 Industries firearm adapters are sold separately Package Contents: A3 Industries Skelestock Skeleton Stock Nylon 1/2in cheek riser 1 modular steel full-rotation QD sling mount