The Geissele Super Duty 5.56 NATO 11.5" 1:7" CHF 08-245S upper is built for anyone assembling a custom AR who wants the foundation dialed in before the rest of the parts go on. A Super Duty Upper mates to a 10.5" MK16 Super Modular Rail through Geissele's center aligning tab, eliminating any chance of rail rotation, the same rail-to-receiver connection USASOC-fielded builds rely on.

This Geissele 11.5 upper runs an 11.5" barrel, cold hammer forged and chrome lined, finished in manganese phosphate rather than a standard coating for real durability under hard use. It's precision machined at Geissele's own North Wales, PA facility, using materials selected specifically for the job rather than pulled from a generic supply chain. A carbine length gas system paired with the Super Compact Gas Block keeps cycling tuned specifically to this barrel length.

As a Geissele Stripped upper, this one leaves BCG, charging handle, and muzzle device selection entirely up to the builder, so the final configuration is exactly what you want it to be rather than whatever came bundled. That's the appeal of starting from a stripped upper in the first place: control over every downstream decision without paying for parts you'd swap out anyway.

Finished in Desert Dirt Color, this Geissele Super Duty 11.5 upper receiver gives a custom build the same quality and craftsmanship running through Geissele's entire lineup, starting from the ground up.

Key Features

• Super Duty upper mates to a 10.5" MK16 rail via center aligning tab
• 11.5" cold hammer forged, chrome-lined barrel, 1:7 twist
• Manganese phosphate coated barrel finish
• Carbine length gas system with Super Compact Gas Block
• Precision machined at Geissele's North Wales, PA facility
• Full-length picatinny top rail for optics and accessories
• No BCG, charging handle, or muzzle device included
• Finished in Desert Dirt Color