Armaspec Self-Retention Castle Nut Features The Armaspec Self-Retention Castle Nut redefines stability and simplicity for an AR-15 or M4 build. Its patented thread locking technology grips the buffer tube threads securely in place eliminating the traditional need for staking the nut or applying thread locker during assembly. This self-retaining design means the nut stays put under recoil and vibration keeping the stock assembly tight through extended use. The result is a cleaner installation process that still delivers the same dependable retention builders expect from a properly staked castle nut. Built from premium grade 7075 aluminum this castle nut combines exceptional strength with reduced overall weight making it a smart choice for lightweight competition or duty builds. The black anodized finish adds corrosion resistance and a durable long-lasting surface that matches most AR-15 and M4 hardware finishes. Designed for quick and easy installation it saves builders time at the bench without compromising performance or long-term durability. The Armaspec Self-Retention Castle Nut is a straightforward upgrade for anyone finishing a stock assembly on an AR-15 or M4 platform rifle. Armaspec Self-Retention Castle Nut Specifications Manufacturer: Armaspec Model: Self-Retention Castle Nut Color: Black Material: Aluminum Finish: Anodized Compatible Hosts: AR-15 / M4 Available At: GrabAGun