1‑1/8"-8 x 4" Stainless Steel 316 B8M Heavy Hex Head Cap Screw, Partial Thread, ASTM A193 Class 1

Manufactured from 316 stainless steel and meeting ASTM A193 Grade B8M, Class 1 specifications, the 1‑1/8"-8 x 4" heavy hex head cap screw is designed for corrosion‑resistant fastening in high‑load industrial and structural applications. The partial‑thread (PT) configuration features an extended unthreaded shank that enhances shear strength and promotes efficient load transfer in stressed bolted joints, making it especially suitable for flanged connections and thick material assemblies. Its 4" length provides solid grip for secure engagement, while the heavy hex head offers increased bearing surface and improved wrench engagement for controlled, high‑torque installation. Commonly specified for marine environments, chemical processing equipment, pressure systems, and outdoor structural assemblies, this fastener delivers dependable performance and long service life in corrosive and moisture‑exposed conditions.