The Dirty Bird 10.3" V2 Upper Assembly is the next iteration in Dirty Bird's Line of Complete Uppers. We wanted to make an upper that could go on an AR Pistol or SBR and be used for a variety of applications, such as: Home Defense, Range Plinking, or Suppressed Fire.Ballistic Advantage 10.3 Classic Series 556 Chrome Lined Carbine Barrel, BABL557103MC, is machined from 4150 Chrome Moly Vanadium and features a chrome lined bore and chamber with a manganese phosphate finish, and phosphate coated M4 feed ramp extension. This 10.3 Classic Series 5.56 Chrome Lined Carbine barrel has been HP and MPI tested to ensure the best in quality and accuracy, and is configured with a carbine length gas system.The Dirty Bird 10.3 5.56 NATO V2 comes equipped with a SureFire 3 or 4 Prong Flash Hider w/ Suppressor Adapter - 5.56 which serves as a rock-solid mounting adapter for SureFire SOCOM Series 5.56 suppressors.The upper is built on a top-tier 7075 forged upper receiver, and fitted with a Dirty Bird SMRS V2 Handguard. Key features of this handguard include: Patented ASAL (Anti-Slip, Anti-Lift) mounting system Included M-LOK QD Mount "Competition Cut" top railThis upper ships with an MOA Guarantee and is covered by the Dirty Bird Limited Lifetime Warranty.