The AR-15 Barrel is an 18" Mid Weight barrel made out of 4150 steel with a parkerized finish, a 1:7 twist rate and a mid-length gas system. The barrel is chambered in .224 Valkyrie. Finished Barrels go through a 100% Inspection Process. Inspections Equipment includes CMMs and Air Gauges for the Bores. {{widget type="Magento\Cms\Block\Widget\Block" template="widget/static_block/default.phtml" block_id="42"}} It is the responsibility of the consumer to ensure all state, local, federal, and ITAR regulations are followed Does not include gas block or gas tube