This unique side folding aluminum stock adapter must be mount to an AR buffer tube style threaded adapter or base and then an AR type buffer tube with a rear stock can be mounted (threaded). May fold to the left or the right. It can be used with any of our AR stock adapters for the Yugo M92/M85. This part number is for side folding adapter only. Fits Commercial and Mil Spec tubes, does NOT work with non folding regular buffers and buffer springs. Locks in the open position and closed. Light duty only, for pistol buffer tube mount only, not for use with arm braces, stabilizer blades or rear stocks.