Magpul Industries X-22 Backpacker Forend, Drop In, Compatible with Ruger 10/22 Takedown with the Hunter X-22 Takedown Stock, Olive Drab Green MAG1066-ODG The X-22 Backpacker Forend is intended for use with additional barrels for rifles currently equipped with the X-22 Backpacker Stock" MAG808. Its minimalist design offers a convenient package without compromising shooting performance. It is compatible with factory and aftermarket barrels up to 0.92" outer diameter. Constructed of a durable advanced polymer" the X-22 Backpacker Forend features a unique locking interface to attach the barrel assembly to the stock body when being transported.