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The Mk4 AR15 Upper Receiver Assembly with Forward Assist for AR-15 builds. Forged mil-spec upper receiver crafted from 7075-T6 aluminum (M4 type). Available in Cerakote finishes; seven options listed by CMMG. This version does not feature an enlarged ejection port. For pistol-caliber builds, the enlarged port version is available as product 55BA290. Lifetime Quality Guarantee.
Specifications:
- Platform: Mk4
- Upper Receiver: Forged 7075-T6 Aluminum M4 Type
- Finish: Cerakote Standard
Specifications
- Manufacturer:
- CMMG
- Category:
- upper-receiver
- Platforms:
- AR-15
- MPN:
- 55BA206
- Required Component:
- Yes
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