The Magpul(R) Enhanced Rubber Butt-Pad” 0.70″ is an optional replacement butt pad for the CTR(R) and MOE(R) Carbine Mil-Spec stocks as well as the original UBR(R)” all STR(R)” ACS-L(TM) and ACS(TM) stocks. It is designed for enhanced shoulder purchase as well as offering slightly improved recoil reduction with its thicker” vented construction. The Enhanced Rubber Butt-Pad can also be installed on Commercial-Spec MOE(R)/CTR(R) stocks” but may prohibit use of fully collapsed position due the extended” slanted back of most commercial-spec receiver extensions. All mounting hardware included. NOTE: Not compatible with MOE(R) Fixed Carbine Stock.