Product Details: AR9 Upper Assembly – 5.5″ / 9mm / 1:10 / Keymod / 160698
➲ Upper Receiver
The foundation of all good ARs is built upon a dependable upper receiver. CBC upper receivers offer best-in-class quality while providing you years of dependable service. Boasting a MIL-SPEC type III hard coat anodized finish and machined from 7075-T6 forged aluminum, this M4 flat-top receiver delivers a lifetime of superior function. You want your AR built upon a solid platform - this receiver gives you the confidence that your AR-15 will function when it counts most.