The HexOne Rifle Buffer Tube (HexOne-R) is precision machined in house from USA sourced raw billet 7075-T7 aluminum. The HexOne-R features a hexagonal design that is much thicker and rugged than a mil-spec receiver extension tube, making it perfect for any rifle length AR platform systems.All HexOne tubes undergo a rugged tumbling process that further strengthens the exterior of the parts while leaving the surfaces smooth and snag free.Edge to Edge OD: 1.4in.Flat to Flat OD: 1.25in.**This model of the Hex Tube lineup is not designed to accept a Pistol Brace, and is not compatible with stocks that accept the standard A2 Rifle Tube.Includes:HexOne Rifle Length Buffer TubeCastle NutEnd Plate