S-91253A302 1/4"-28 x 7/8" ASTM F835 Alloy Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Exceptional strength and durability with 130,000 psi tensile strength and Rockwell C39 hardness for reliable performance in high-stress applications
• Precise thread engagement through Class 3A thread fit and UNF fine threading, ensuring secure fastening and vibration resistance
• Corrosion-resistant black-oxide finish on alloy steel for enhanced longevity in demanding industrial environments
• Easy installation and removal with 5/32" hex drive and standard flat head profile, compatible with common tools
• Full threading capability providing maximum grip along the entire 7/8" length for superior holding power
• 82° countersink angle design allowing for flush mounting in precision applications
• Regulatory compliance assurance meeting ASTM F835 specifications and environmental standards including RoHS 3 and REACH

Professional Applications & Engineering Value

These 1/4"-28 UNF flat head screws deliver critical engineering solutions for industrial assembly challenges where precision and reliability are paramount. The black-oxide alloy steel construction provides superior corrosion resistance while maintaining the 130,000 psi tensile strength necessary for structural applications. The Class 3A thread fit and UNF fine threading ensure tight tolerances that prevent loosening under vibration, making them ideal for machinery, automotive components, and precision equipment. The combination of fully threaded design and 82° countersink angle enables flush mounting in critical applications where surface profile and maximum thread engagement are essential. These hex drive screws with 5/32" drive size offer efficient installation in confined spaces, reducing assembly time while maintaining the high performance standards required in industrial fastening systems.

Specification Summary & Compliance

This flat head screw features precise dimensional accuracy with Class 3A thread fit per UNF standards, ensuring superior threading performance. Manufacturing complies with ASTM F835 specifications for consistent quality and reliability. The product meets stringent environmental regulations including RoHS 3 (2015/863/EU) compliance and REACH (EC 1907/2006) compliance, confirming adherence to international safety and environmental standards for industrial components.