Sylvan Arms SA5 Folding Stock Adaptor 4140 Steel Black. Turn AR's into a compact concealable platform with a folding stock adapter built to enhance rifles. The SA5 is lightweight and 250percent stronger than the 4th gen adapter. As with the Gen4 adapter choose from a left folding or right folding option depending on needs. Does NOT work with Tippmann 22 or LWRC Pistols. Specifications for Sylvan Arms SA5 Folding Stock Adaptor: Manufacturer: Sylvan Arms Color: Black Gun Make: AR Platform Gun Model: AR-9 AR-15 Gun Type: Rifle Fabric/Material: Steel Threads per Inch: 1-3/16x16 Stock/Brace Material: 4140 Steel Features of Sylvan Arms SA5P-R SA5 Folding Stock Adaptor 4140 Steel Black AR15 Compatible 4140 Steel and only 9.4 ounces Right or Left Fold Versions Adjustable Hinge Tension Improved and Hardened Buffer Pin 2 QD attachment points Improved Locking Mechanism Standard 1-3/16 x 16 threading Includes all tools needed for easy installation Includes a 1045 Steel Bolt Extension No additional parts are required for standard AR15 Bolt Carrier Groups Installs in under 5 minutes. Package Contents: Sylvan Arms SA5P-R SA5 Folding Stock Adaptor 4140 Steel Black What firearm models does the manufacturer say Sylvan Arms SA5 Folding Stock Adaptor is compatible with? The manufacturer says that Sylvan Arms SA5 Folding Stock Adaptor is compatible with AR-15 AR-9Sylvan Arms SA5P-R SA5 Folding Stock Adaptor 4140 Steel Black