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Maxim Defense MDX 508 5.56 Mil-Spec Complete Upper - 8.5" Urban Grey

AR-15 Complete Upper Receiver

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Maxim Defense MDX 508 5.56 Mil-Spec Complete Upper - 8.5" Urban Grey


The MDX508 upper receiver is now available as a direct upgrade to your existing Mil-Spec lower receiver. It features an 8.5” barrel making it ideal for close-quarters situations. The included HATEBRAKE™ increases reliability and is tucked under the 9.5” handguard. These upper receiver groups ship complete, including a Maxim Defense Mil-Spec or SCW bolt carrier group, Radian Raptor charging handle, and Maxim Defense hand stop, ready to shoot right out of the box.


  • Features:
    1. Increased reliability due to included HATEBRAKE™
    2. Armorer level adjustable gas block
    3. M-slot compatible handguard
    4. Military-grade materials [17-4 Stainless Steel, 7075 and 6061 Aluminum]
    5. HK height rail for a more rigid upper receiver
    6. Installs on any Mil-Spec lower receiver
    7. Comes with Mil-Spec BCG
    8. Includes one 30rd C Products Magazine


  • Specifications:
    Weight: 3 lbs 10 oz
     Barrel Length: 8.5”
     Calibers: 5.56 NATO
More Information
SKU MXM-48112
Product Type AR-15 Complete Upper Receiver
Manufacturer Maxim Defense
Color Urban Grey
Mount M-LOK
Barrel Length 8.5"
Caliber 5.56 NATO
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