Phase 5 Weapon Systems Inc Hex-2 AR-15 Pistol Buffer Tube f/Tailhook Mod1 Brace Black HEX-2-TAILHOOK MOD1. Combining This Tube With The Tailhook Mod1 Gives Your Ar Pistol Build The Look And Function You'Ve Been Looking For. The Hex-2 Is A Heavy-Duty...