The Intrafuse T6 Buttstock Assembly by TAPCO features a 6-Position collapsible buttstock stock assembly built to exacting tolerances and includes a metal sling swivel. Each stock body is machine qualified to the exact dimension of the impact extruded 7075 T6 aluminum extension tube, for a no-rattle fit. This process allows for a smooth action and snug fit between the stock body and the extension tube. Extension tube threads are rolled on, a Mil-Spec process superior to the standard thread "cutting" process. The inside of the extension tube is coated with Mil-Spec dry film lubricant that not only keeps the action quieter; it reduces metal-on-metal contact, extending the service life of your buffer. While most other tubes are anodized or have no finish, the outside of the TAPCO tube is grit blasted to leave a non-reflective surface, then coated in Mil-Std 171 Lusterless Black for a smooth matte finish. The extension tube is 100% made and finished in the U.S and is supplied with a certificate of origination; you won't find that anywhere else!