The increased diameter of the barrel was designed for extended fully-automatic fire and heat control. All AUG HBAR barrels ship with the classic, aggressive vertical recoil mitigation muzzle device and adjustable-cant bipod. Like all AUG barrels currently being produced, these barrels are cold-hammer forged in Steyr, Austria before being machined and assembled in the USA.
Check local states laws if unsure of compliance before purchasing.