The Aero Precision M5 .308 Complete Lower Receiver stands as a formidable foundation for any custom big-bore AR rifle. Engineered with precision, this lower receiver is designed to seamlessly integrate with standard AR 308 components and magazines, ensuring compatibility while offering the user the flexibility to personalize their build. One of its standout features is the rear takedown pin detent hole, which comes threaded for a 4-40 set screw. This thoughtful design element simplifies assembly and enhances reliability—no more worries about lost detents during disassembly. Additionally, the bolt catch has been expertly crafted to be threaded for a screw pin; this eliminates the need for roll pins that can often complicate installation. The integrated trigger guard provides not only functionality but also an aesthetic appeal, streamlining your rifle’s profile without sacrificing comfort or performance. Selector markings are thoughtfully positioned to accommodate safety selectors at various angles: 45°, 60°, or even 90°. For those who prefer enhanced control in critical situations, it accepts Battle Arms Development short throw safety selectors while remaining compatible with any standard selector on the market. Moreover, you’ll find no gap when using aftermarket pistol grips—a detail that speaks volumes about Aero Precision's commitment to quality and user satisfaction. Included with your purchase are essential components such as: - The M5 Lower Receiver finished in FDE Cerakote for superior durability - An M4 Stock in Black providing stability during use - A classic A2 Grip also in Black ensuring solid handling - A mil-spec lower parts kit containing all necessary parts - Carbine receiver extension paired perfectly with - A .308 carbine buffer and spring In summary, whether you're building from scratch or upgrading an existing platform, the Aero Precision M5 .308 Complete Lower Receiver offers unmatched versatility and ease of use. It embodies both function and form—an ideal choice for discerning marksmen seeking excellence in their firearm endeavors.