Description The Aero Precision EPC Buffer Kit features our Enhanced Carbine Buffer Tube and our 7.7oz buffer and spring specifically optimized for use in the Aero Precision EPC. NOTE: The 7.7oz EPC buffer, it is not intended for use in AR15 or M5 platforms. The additional length and weight will not allow for proper cycling of standard platforms. Includes: EPC Buffer 308 Carbine Buffer Spring Enhanced Carbine Buffer Tube Mil-Spec Receiver End Plate Mil-Spec Castle Nut Stock NOT Included Note: For use in a 40S&W, 10mm, or 45ACP build we recommend the use of a heavier buffer spring.