The Magpul™ CTR® Mil-Spec Stock is a great and affordable alternative to the standard collapsible stock as found on the old style CAR-15 platforms. Fits Mil-Spec lower receiver extension tubes only. Friction lock holds your stock in the position that best suits your shooting position. Easily adjustable with just a quick squeeze of the lever. Has several different locations for rear sling attachment.Friction lock will depend on the extension tube wear.