This 5-piece kit supplies the receiver-extension hardware for an AR pistol build. It uses a pistol-length buffer tube (roughly 7.3") sized to accept a pistol brace rather than a collapsible carbine stock, and it ships with the buffer and spring that cycle the action. Everything you need to set up the rear of an AR pistol lower except the brace itself.

Features:

• AR pistol receiver-extension (buffer tube) kit, 5 pieces
• Pistol-length buffer tube, approximately 7.3"
• Recoil buffer and buffer spring included
• End plate and castle nut included
• Mil-spec diameter

This is a pistol-brace tube and will not accept a collapsible carbine stock. The pistol brace and lower parts are not included. Mil-spec diameter, so pair it with a mil-spec brace.