Aero Precision APAR308503A M5 308 Winchester/7.62 NATO Brl Finish The M5 .308 Assembled Upper Receiver comes with both the port door and forward assist hardware preinstalled. Forged from 7075-T6 aluminum, this assembled upper is precision machined to accept standard .308 components and is the ideal upper for your big bore build. It includes M4 Feedramps,.2795 takedown pin holes (DPMS size), and DPMS High Profile (.210) Tang). This addembled upper receiver is finished in anodized black. Type: Stripped Caliber: 308 Winchester/7.62 NATO Sights: None, Optic Ready Barrel Length: N/A Receiver Description: 7075-T6 Aluminum M4 Receiver Finish: Black Hard Coat Anodized