Whether you're building from the ground up or replacing existing parts this is the receiver extension build kit you need. Includes M4 Buffer Tube Castle Nut TAPCO End Plate Sling Adaptor Buffer and Recoil Spring. Available in Mil-Spec and commercial variations. - M4 Buffer Tube - Castle Nut - TAPCO End Plate Sling Adaptor - Buffer - Stainless Steel Recoil Spring
Determined at checkout.