Barrel: 20" Chrome Moly vanadium steel, chambered in 5.56 NATO, with a 1:7 twist rate, M4 barrel extension, and a rifle length gas system. The profile barrel is nitride finished for accuracy and durability. The barrel is finished off with an .750" diameter F-marked Front Sight Base, PSA Classic Handguards, and an A2 flash hider. Upper: Forged 7075-T6 A3 AR upper is made to MIL-SPECS and hard coat anodized black for durability. May have T marks and features a Mil-Spec finish. These uppers are made for us right here in the USA by a Mil-Spec manufacturer. Carry Handle Assembly: PSA Mil-Spec Carry Handle - Mil-Spec height carry handle for flat top AR-15, M16A4, M4, M4A1 rifles and carbines. Compatible with taller F marked front sight bases. Machined from 7075T6 forgings, hard coat anodized, staked thumb screws, A2 aperture, 6/3 windage drums.