S-92620A278 1 1/4"-12 x 5" ASME B18.2.1, SAE J429 High-Strength Grade 8 Steel Hex Head Screws

Key Features & Benefits at a Glance

• Exceptional load-bearing capacity with 150,000 psi tensile strength for reliable performance in high-stress industrial environments
• Superior corrosion resistance provided by zinc yellow-chromate plating, extending service life in demanding conditions
• Precise thread engagement with UNF fine threads and Class 2A fit ensuring secure fastening and vibration resistance
• Enhanced durability through Rockwell C33 hardness and Grade 8 classification for long-term reliability
• Optimized torque transmission via external hex drive and 1 7/8" head width for efficient installation and removal
• Versatile partial threading design allowing for both clamping and alignment functions in complex assemblies
• Regulatory compliance assurance meeting ASME B18.2.1 standards and environmental regulations including RoHS 3 and REACH

Professional Applications & Engineering Value

These Grade 8 hex head screws deliver critical engineering solutions for heavy machinery, structural frameworks, and industrial equipment where failure is not an option. The combination of 150,000 psi tensile strength and Rockwell C33 hardness ensures exceptional resistance to shear forces and permanent deformation under extreme loads. The zinc yellow-chromate plating provides superior corrosion protection in harsh environments, while the UNF fine threads with Class 2A fit maintain precise clamping force and prevent loosening from vibration. The partially threaded design offers flexibility in applications requiring both threaded engagement and smooth shank alignment. These industrial fasteners are engineered to meet the rigorous demands of construction equipment, agricultural machinery, and heavy vehicle assemblies where reliability and durability are paramount.

Specification Summary & Compliance

Manufactured to exacting ASME B18.2.1 and SAE J429 standards, these hex head screws feature precise Class 2A thread fit tolerances and UNF fine threading with 1 1/4"-12 specification. The 5" length includes a minimum 2 3/4" thread length for optimal engagement. Full compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations ensures safe usage across various industrial sectors while maintaining the highest quality standards for inch system fasteners.