Constructed of 6061-T6 aluminum with meticulous care given to each cut, the JE Machine Mil-Spec buffer tubes are sure to be the perfect choice for any range toy or utility build. FeaturesMil-SpecType II anodized6061-T6 aluminum6 positions3.8 ozInner diameter: 1"; Outer diameter: 1.145"; Length is 7.15" IncludesDPMS Platform Mil-Spec Buffer Tube (6061 T6 Grade Aluminum)SpringBlack BufferCastle NutStandard End Plate