1"-8 x 3‑1/4" Stainless Steel 304 B8 Heavy Hex Head Cap Screw, Partial Thread, ASTM A193 Class 1

This 1"-8 x 3‑1/4" heavy hex head cap screw is manufactured from Type 304 stainless steel and meets ASTM A193 Grade B8, Class 1 specifications, making it a reliable choice for heavy industrial and structural fastening applications requiring corrosion resistance. The partial‑thread (PT) design incorporates an unthreaded shank section that improves shear strength and ensures proper alignment in high‑load bolted joints, particularly in flanged connections and thick material assemblies. Its 3‑1/4" length supports secure fastening through substantial components, while the heavy hex head provides increased bearing surface and enhanced wrench engagement for controlled torque application. Commonly used in piping systems, pressure connections, equipment mounting, and structural fabrication, this fastener delivers dependable resistance to rust, oxidation, and environmental exposure for long‑term performance in indoor, outdoor, and moderately corrosive environments.