Griffin Armament MK1 AR-15 Assembled Upper Receiver

Upgrade your AR-15 build with the Griffin Armament MK1 Assembled Upper Receiver, a precision-crafted component designed for reliability and seamless integration. This mil-spec upper arrives ready for barrel installation, featuring a pre-installed forward assist and ejection port door to streamline your assembly process and deliver professional-grade performance from the start. Key Features Forged 7075-T6 aluminum construction provides exceptional strength and lightweight durability for demanding tactical applications. Mil-spec M16/M4 machining with M4 feedramps ensures compatibility with a wide range of barrels and reliable feeding in high-volume use. Pre-assembled forward assist and ejection port door saves time and reduces the need for additional tools or expertise during build. Type III hardcoat anodized finish in Black, Terra Brown, or Warhawk Green offers corrosion resistance and a professional appearance that matches various firearm aesthetics. Specifications Material: 7075-T6 Aluminum Finish: Mil-A-8625F, Type III, Class 2 Anodized Weight: 8.5 oz Feedramps: M4 Assembly: Includes forward assist and ejection port door Why Choose This Product Builders seeking a dependable foundation for their AR-15 appreciate the MK1’s exacting tolerances and thermal-fit barrel extension compatibility, which promotes consistent accuracy and longevity. Its forged design withstands rigorous use while maintaining mil-spec standards for drop-in compatibility with standard lowers and components. Whether completing a custom build or replacing an existing upper, this receiver addresses common pain points like assembly complexity and finish quality without unnecessary extras.