Aim Sports AR5CUB9 Complete Build Kit 5.56 NATO 10.5in Upper Optic Ready M-LOK

The Aim Sports AR5CUB9 Complete Build Kit delivers a ready-to-build upper assembly for 5.56x45mm NATO platforms, combining a 10.50" black nitride barrel with a 4150 Chrome Moly vanadium steel profile, a 7075-T6 aluminum black anodized receiver, and a 10" M-LOK handguard for AR-15 compatibility. Optic-ready by design, this kit provides practical options for contemporary rifle configurations while maintaining a clean, durable profile suitable for range days or field use. The barrel features a 1:8 twist rate and a Black Nitride finish that enhances wear resistance and corrosion protection, pairing well with standard 5.56 ammunition for reliable performance. The receiver and handguard finish are both Black Hard Coat Anodized, delivering a cohesive aesthetic and added durability during hard use. This complete upper assembly integrates smoothly into compatible AR-15 builds, offering a solid foundation for precision shooting, home defense setups, or training applications. Built by Aim Sports, the kit emphasizes modularity, enabling shooters to outfit optics, accessories, and devices suited to their preferred shooting discipline. With meticulous manufacturing and practical specifications, the AR5CUB9 kit supports consistent accuracy, dependable cycling, and straightforward installation for experienced builders and enthusiasts alike.