The A1 9mm upper features a 11.5" 41V50 CrMo steel barrel in a Gov profile. The barrel has a melonite nitride finish including the bore. The standard configuration includes a "A2" marked front sight base and carbine type hand guards. Bolt is made by CMMG and Colt/Glock style compatible. The barrel extension on a 9mm barrel is part of the overall length of the barrel. A 11.5 will have an a shorter appearance than a similar 5.56 barrel.