Ergo M4 Receiver Castle Nut, Black

This versatile component is engineered to seamlessly integrate with a wide range of AR platforms, including the AR-15 and all its variants. Designed for compatibility with commercial, military and hybrid buffer tubes, it ensures a perfect fit and reliable performance across diverse applications. Whether you're outfitting a tactical setup, upgrading a sporting rifle or enhancing a custom build, this component delivers the adaptability and precision you need. Built to meet rigorous standards, it o