This BCA AR-15 Barrel is 14.5" M4 Contour Barrel made of 4150 Chrome Moly Vanadium with a parkerized finish, carbine length gas system with a 1:8 twist. The barrel is chambered in 5.56 NATO and machined in M4 feed ramps in the barrel extension. All 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