The strike industries 7 position advanced receiver extension brings an updated aesthetic and increased functionality to an often neglected, yet highly important component of the ar15/ar10 weapon system.The scalloped surfaces decrease friction with tight fitting stocks,and shaves weight while retaining mass in critical stressed areas.Further enhancements include a supported buffer retaining tab that also serves to more easily index your receiver extension.Features 7-position mil-spec diameter buffer tube, fits onto any standard ar15 receiver, finer length of pull adjustment, supported buffer retainer and compatible with strike industries pit viper stock.Finish: Red AnodizedType: Extension TubeModel: Advanced Receiver ExtensionSize: Mil-SpecMaterial: Aluminum