S-91251A103 2-56 x 3/4" ASTM A574 Alloy Steel Socket Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength (170,000 PSI) for reliable performance in high-stress applications
• Superior corrosion resistance with black-oxide coating, extending service life in demanding environments
• Precise Class 3A thread fit ensures secure, vibration-resistant fastening in critical assemblies
• High hardness rating (Rockwell C37) provides excellent wear resistance and durability
• Standard hex drive design allows for easy installation with common tools in confined spaces
• Coarse UNC threading enables quick assembly and disassembly for maintenance efficiency
• Full thread coverage along the 3/4" length maximizes grip and load distribution

Professional Applications & Engineering Value

This black-oxide alloy steel socket head cap screw delivers critical performance where standard fasteners fail. The combination of 170,000 PSI tensile strength and Rockwell C37 hardness makes it ideal for high-vibration machinery, precision equipment, and structural applications requiring reliable clamping force. The black-oxide surface treatment provides essential corrosion protection in industrial environments while maintaining dimensional stability. With UNC coarse threads and Class 3A fit, these screws ensure rapid assembly in production lines and secure fastening in automotive, aerospace, and heavy equipment applications where thread integrity is paramount.

Specification Summary & Compliance

This socket head cap screw features 2-56 UNC coarse threads with Class 3A precision tolerance for consistent fit and performance. Manufactured to ASTM A574 specification for high-strength alloy steel socket head cap screws. Fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring safe use across global industrial markets.