Product Description The WMD Guns NiB-X Stripped Upper Receiver is a precision-engineered AR-15 upper receiver designed to serve as an outstanding building block for a durable, high-performance rifle build. Forged from 7075 T6 aluminum to Mil-Spec standards, this A3/A4 upper receiver features M4 feed ramps for reliable feeding across a wide range of ammunition. Its defining feature is WMD&';s proprietary NiB-X (Nickel Boron) coating, applied comprehensively inside and out, which creates an exceptionally tough, ultra-smooth surface that dramatically reduces friction, resists wear, and provides natural lubricity. Whether you are building a custom AR-15 from scratch or upgrading an existing platform, this stripped receiver delivers the quality, consistency, and longevity that serious builders demand. Product Highlights Forged 7075 T6 aluminum construction machined to Mil-Spec tolerances for superior strength and long-term reliability NiB-X (Nickel Boron) coating applied inside and out for outstanding wear resistance and self-lubricating surface performance A3/A4 configuration with M4 feed ramps ensures reliable feeding and compatibility with a broad range of 5.56 NATO loads Stripped design provides maximum flexibility to customize your AR-15 build with your choice of components Compatible with standard AR-15 parts and accessories, making it an ideal foundation for any custom build Specs Brand: WMD Guns MPN: 1-NIBXUF UPC: 855899003225 Caliber: 5.56x45mm NATO Type: Stripped Upper Receiver Configuration: A3/A4 Feed Ramps: M4 Material: Forged 7075 T6 Aluminum Finish: NiB-X (Nickel Boron) Length: 8.75" Width: 4.75" Height: 2.25" Weight: 0.5 lbs Disclaimer: We strive to provide accurate and up-to-date product descriptions, specifications, and images; however, errors or omissions may occasionally occur. We are not responsible for any inaccuracies or discrepancies in the content provided. If you notice anything incorrect or unclear, please contact us so we can correct it. When in doubt, we recommend verifying details directly with the product&';s manufacturer.