This .308 chambered (DPMS style) 16 inch barrel is machined from 416R Stainless Steel with a QPQ Corrosion Resistant finish. The Premium Series Barrels are HP and MPI tested, ensuring the best in quality and accuracy. Hanson Series Barrels feature a proprietary BA Hanson profile and include a pinned lo-pro gas block. Hanson barrels are not designed to work with aftermarket piston kits.