The Magpul Enhanced Rubber Butt-Pad 0.70″ is an optional replacement butt pad for the CTR and MOE Carbine Mil-Spec stocks as well as the original UBR” all STR” ACS-L and ACS 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/CTR 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 Fixed Carbine Stock.