The AR-15 Billet Castle Nut features precision billet construction with a durable black anodized finish for enhanced corrosion resistance and professional appearance.AR-15 Billet Castle NutPrecision machined from billet aluminumBlack anodized finish for durabilityCompatible with AR-15 platform riflesProfessional grade constructionEssential component for securing the buffer tube assembly on AR-15 builds and modifications providing reliable performance and a clean tactical appearance.