This Vltor A5 Recoil System AR-15 Receiver Extension Tube is an improved buffer tube design that features 7 different positions to provide the ultimate in stock adjustability. The tube's Shortest Length of Pull position is as compact as a fully collapsed M4 Carbine Buttstock while its Longest 7th Position stretches stock length to slightly longer than that of an M16A2 Fixed Stock. Manufactured from Impact Extruded 7075-T6 Aluminum and given a durable Hard Anodized Finish, the A5 Buffer Tube is compatible with Mil-Spec Diameter, Lengthened Collapsible Stocks such as the Vltor EMOD.

The Vltor A5 Recoil System was developed at the request of the US Marine Corps as a potential future upgrade to replace the current A2 Fixed Stock used on the M16A4. The new recoil system consists of the Longer A5 Receiver Extension Tube with 7-Positions, a Longer and Specially Weighted A5 Buffer, and a standard Rifle Length Buffer Spring. The A5's enhancements to the AR-15 operating system result in a rifle that exhibits the increased Reliability, Smooth Action Impulse and Performance for which the A2 Fixed Stock Assembly is renowned, while also offering the benefits of Full Adjustability and greater Ergonomics attributed to the M4 Collapsible Stock arrangement. The A5 Recoil System is compatible with both direct gas impingement and piston operated AR-15 platforms, and may be fine-tuned to alter a rifle's recoil impulse or cyclic rate by changing to a different weight A5 Buffer (5 weights available).