S-91251A644 3/8"-16 x 5" ASTM A574 Alloy Steel Socket Head Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with black-oxide coating, ideal for harsh industrial environments
• Superior tensile strength (170,000 psi) ensures reliable performance in high-stress applications
• Precision Class 3A thread fit provides consistent, secure fastening with minimal play
• Rockwell C37 hardness delivers excellent durability and wear resistance
• Coarse UNC threading enables quick assembly and reduced cross-threading risk
• Partially threaded design offers optimal grip and alignment in varied material thicknesses
• Hex socket drive (5/16") allows high-torque installation in confined spaces

Professional Applications & Engineering Value

These black-oxide alloy steel socket head cap screws are engineered to solve critical fastening challenges in demanding industrial settings. The UNC coarse thread design combined with Class 3A precision threading ensures rapid installation while maintaining vibration resistance in machinery, automotive, and heavy equipment applications. The black-oxide surface treatment provides reliable corrosion protection without compromising dimensional accuracy, making these partially threaded fasteners ideal for applications requiring both clamping force and precise alignment. With their 170,000 psi tensile strength and Rockwell C37 hardness, they deliver consistent performance in high-load assemblies where failure is not an option.

Specification Summary & Compliance

This 3/8"-16 UNC socket head cap screw features Class 3A thread fit for precision tolerance, 5" length with minimum 1-1/4" thread length, and 9/16" head diameter. Manufactured to ASTM A574 specification and fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring both mechanical reliability and regulatory adherence for global industrial applications.