1‑1/8"-8 x 5‑1/2" Stainless Steel 316 B8M Heavy Hex Head Cap Screw, Partial Thread, ASTM A193 Class 1

Manufactured from 316 stainless steel and certified to ASTM A193 Grade B8M, Class 1, the 1‑1/8"-8 x 5‑1/2" heavy hex head cap screw is designed for corrosion‑resistant fastening in high‑load industrial and structural applications. The partial‑thread (PT) configuration incorporates an extended unthreaded shank that enhances shear strength and ensures efficient load transfer across heavily stressed bolted joints, making it especially effective for flanged connections and thick material assemblies. Its 5‑1/2" length provides substantial grip for deep engagement through large structural sections, while the heavy hex head delivers increased bearing surface and improved wrench leverage for controlled, high‑torque installation. Commonly specified for marine environments, chemical processing equipment, pressure systems, and outdoor structural installations, this fastener delivers dependable performance and long service life in corrosive and moisture‑exposed conditions.