Geissele Super Duty Mod 1 Upper Receiver Group 5.56 NATO 13.9" – AR-15 Platform DDC

The Geissele Super Duty Mod 1 Upper Receiver Group delivers a complete 5.56 NATO solution for AR-15 pattern lowers. Built around a 13.9-inch cold hammer-forged barrel, this configuration offers compact maneuverability while maintaining sufficient velocity for effective terminal performance at intermediate ranges. The Desert Dirt Color finish provides corrosion resistance with a distinctive appearance that sets it apart from standard black anodizing.

Manufactured from 7075-T6 aluminum with Type III hard-coat anodizing in DDC, this upper receiver group includes Geissele's proprietary barrel extension, gas block, and bolt carrier group. The 13.9-inch barrel length is commonly selected for pin-and-weld projects to achieve the 16-inch legal minimum overall barrel length when paired with appropriate muzzle devices. Installation requires standard AR-15 armorer's tools and torque specifications per manufacturer guidelines.

• Caliber: 5.56 NATO
• Type: Complete Upper Receiver Group
• Compatible Lower: AR-15 Pattern
• Barrel Length: 13.9 inches
• Material: 7075-T6 Aluminum
• Finish: Desert Dirt Color (DDC) Type III Hard-Coat Anodized
• Includes: Barrel, bolt carrier group, charging handle, gas system
• Installation: Drops onto mil-spec AR-15 lower receivers