The Geissele Super Duty 5.56 NATO 11.5" 1:7" CHF Bbl Black Stripped Upper Receiver w/10.5" M-LOK MK16 SMR carries the craftsmanship Geissele's whole lineup is known for, built around a genuine center-tab mated rail system rather than a standard clamp-on handguard. The Super Duty upper receiver connects to the 10.5" MK16 rail through Geissele's center aligning tab, removing any chance of rail rotation, something a lot of shooters only appreciate after dealing with a rail that's worked loose on a lesser upper.

M-LOK slots run the rail at the 3, 6, and 9 o'clock positions, giving real flexibility for mounting lights, grips, or other accessories, while a full 12 o'clock picatinny rail handles optics and anything else that needs a true 1913 interface. This Geissele MK16 setup is the same rail family USASOC operators rely on, not a scaled-down civilian version.

The barrel driving this Geissele 11.5 Upper is 11.5", cold hammer forged and chrome lined with a 1:7 twist, finished in manganese phosphate for real corrosion resistance beyond a standard coating. It's precision machined at Geissele's own facility in North Wales, PA, using materials sourced and vetted specifically for the job, not pulled from a generic supply chain.

As a Geissele Stripped Upper, this one leaves the BCG, charging handle, and muzzle device selection up to the builder, giving full control over the final configuration while starting from a foundation that's already dialed in.

Key Features

• Super Duty upper mates to a 10.5" MK16 rail via center aligning tab
• M-LOK slots at 3, 6, and 9 o'clock positions
• Full-length 12 o'clock picatinny rail for optics and accessories
• 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
• No BCG, charging handle, or muzzle device included