S-90344A116 1/4"-20 x 1" ASME B18.3, ASTM A574 Socket Head Screws with Flat Washer

Key Features & Benefits at a Glance

• Superior corrosion resistance with black-oxide finish on both screw and washer for extended service life in harsh industrial environments
• Exceptional mechanical strength with 170,000 psi tensile strength and Rockwell C39 hardness for heavy-duty applications
• Precision thread engagement with Class 3A fit and UNC coarse threads ensuring reliable fastening and vibration resistance
• Integrated load distribution through the flat washer design that prevents surface damage and maintains joint integrity
• Optimized installation efficiency with hex socket drive allowing high torque application in confined spaces
• Full-threaded design providing consistent clamping force along the entire 1" length for secure connections
• Regulatory compliance assurance meeting both performance standards and environmental regulations for global supply chain compatibility

Professional Applications & Engineering Value

This black-oxide alloy steel socket head cap screw delivers critical performance advantages for demanding industrial applications. The combination of 170,000 psi tensile strength and Rockwell C39 hardness ensures reliable performance in high-stress environments including heavy machinery, automotive assemblies, and industrial equipment. The integrated flat washer provides superior load distribution, preventing surface damage to connected materials while the UNC coarse threads with Class 3A fit offer excellent vibration resistance and quick assembly. The hex socket drive enables high-torque installation in space-constrained applications, making it ideal for precision engineering applications where reliability and durability are paramount. The black-oxide surface treatment enhances corrosion resistance without compromising dimensional accuracy.

Specification Summary & Compliance

Manufactured to ASME B18.3 specifications with Class 3A thread fit for precision applications. Features 1/4"-20 UNC coarse threads in right-hand direction with full threading along the 1" length. The assembly includes a flat washer (1/2" OD, 1/16" thickness) manufactured from black-oxide steel. Compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations. Material certification includes ASTM A574 specification for alloy steel socket head cap screws.