Platform | Mk4 |
Upper Receiver | Billet 6061 T6 Aluminum |
Finish | Cerakote Standard |
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
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

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AR Parts Notice - State/local restrictions may apply in CT, DC, IL, MA, NJ, NY, or WA. Customers must review our Shipping Policy prior to ordering.
Upper Receiver Assembly, Mk4/AR15
Expertly crafted from aircraft grade aluminum, CMMG® Mk4/AR15 upper receiver assemblies come with our ZEROED® Polymer Dust Cover pre-installed. Available in seven different Cerakote finishes, this upper receiver omits the forward assist for those looking for a sleek and stylish base to start a new AR15 build.
Lifetime Quality Guarantee
We aim to please, that’s why every CMMG product is backed by our Lifetime Quality Guarantee against material and workmanship defects. Learn More.