M4 Tube Assembly

Machined MIL-SPEC Aluminum Receiver Extension Tube Kit accepts All M4-style MIL-SPEC Adjustable Carbine Buttstocks and Most Commercials.


  • Six Precision-Machined Notches On the Underside Provide Plenty of Options for Setting Length-Of-Pull.
  • Perfect for a Custom Build, Installing a MIL-SPEC or Commercial Stock on a Civilian Carbine, or Updating a Fixed-Stock Rifle With an Adjustable M4 Stock
  • Machined From a Lightweight Aluminum Extrusion Then Hard Coat Anodized, and Dry Film Lube-Coated Inside for Smooth Movement of the Buffer and Buffer Spring
  • Provided Carbine Recoil Spring and Buffer, Lock Ring, and the TSA Receiver Plate