Geissele Super HBAR MOD1 5.56mm 14.5" Complete Upper 08-616S is a heavy-barrel upper assembly engineered for rugged durability and sustained accuracy, built around a cold hammer forged, chrome-lined 14.5" barrel with an .812" gas journal and 1:7 twist. That thicker gas journal is a step up from the standard .750" Heavy Profile found on other Super Duty barrels, giving this Geissele Super HBAR Upper even more mass to resist barrel whip during extended strings of fire. A mid-length gas system through a Super Compact Gas Block keeps cycling smooth despite the added barrel mass, and the pinned-and-welded 5/8x24 muzzle device reaches a legal 16" overall length. This Geissele 14.5 upper carries Geissele's MK16 M-LOK free-float rail, giving builders a rigid platform for optics and accessories without needing to worry about rail rotation under hard use. Finished in Desert Dirt Color with full Picatinny rail surfaces, this Geissele Super duty 14.5 upper is optics-ready and compatible with any mil-spec AR-15 lower. It ships complete with a BCG and charging handle, so the core components for a full build are already accounted for. Key Features: 14.5" cold hammer forged, chrome-lined barrel, 1:7 twist, .812" gas journal Mid-length gas system, Super Compact Gas Block Pinned & welded 5/8x24 muzzle device to 16" overall length MK16 M-LOK free-float rail Includes bolt carrier group and charging handle Full Picatinny rail surfaces, optics-ready Desert Dirt Color finish Fits any mil-spec AR-15 lower receiver This Geissele Super Duty MOD 1 upper hands builders a heavier-than-standard barrel profile for shooters who want maximum sustained-fire durability in a legal-length configuration. Geissele Super HBAR MOD1 Complete Upper 5.56mm 14.5" Bbl (.812 Journal, 5/8x24) P& W DDC Complete Upper Receiver 08-616S