1"-8 x 3‑1/4" Stainless Steel 316 B8M Heavy Hex Head Cap Screw, Partial Thread, ASTM A193 Class 1

Manufactured from 316 stainless steel and conforming to ASTM A193 Grade B8M, Class 1, the 1"-8 x 3‑1/4" 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 unthreaded shank section that enhances shear strength and promotes efficient load transfer in stressed bolted joints, making it well suited for flanged connections and thick material assemblies. Its 3‑1/4" length provides additional grip for deeper engagement, while the heavy hex head offers increased bearing surface and improved wrench engagement for precise torque control during 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.