The Geissele Super Duty 16" Heavy Barrel (.750 Journal) Black stripped upper receiver is a premium AR‑pattern upper designed as a drop‑in core for performance rifle builds. It features a rugged 16‑inch cold hammer forged, chrome‑lined barrel with a 1:7 twist and a mid‑length gas system with a Super Compact gas block for smooth, reliable cycling. Finished in durable anodized black, this stripped upper includes the barrel and gas system installed, and is ready for your choice of bolt carrier group, charging handle, muzzle device, and handguard. Built with Geissele’s heavy‑duty construction and tabbed rail interface, the 08‑660B makes an excellent foundation for custom precision, duty, or range‑oriented rifles.