Utg pro 6-position mil-spec stock assembly is built for heavy-duty operations with the tightest tolerance control.The polymer stock is made from impact resistant high-strength material the mil-spec diameter extension tube is made from aircraft aluminum with rolled threads fde cerakote applied for best corrosion and wear resistance.The stock assembly is complete with action spring buffer assembly tear-drop ring and castle nut.Proudly made in usaType: Buttstock KitFirearm Type: AR-PlatformFirearm Model: AR-15Material: Polymer w/Aluminum TubeFinish: BlackPositions: 6Tube Included: Yes