This is a Factory Aero Precision M5 Complete Lower Receiver is the perfect base for your custom big-bore AR build.

Features:
*Works with standard AR 308 components and magazines
*Rear takedown pin detent hole is threaded for a 4-40 set screw
*Bolt catch is threaded for a screw pin (no roll pin needed)
*Integrated trigger guard
*Selector markings will work with 45, 60 or 90 degree safety selectors
*No gap with aftermarket pistol grips

Includes:
*Aero Precision M5 Lower Receiver
*A2 Grip
*Lower parts kit
*Receiver extension
*.308 carbine buffer and spring
*These parts are installed from the factory