S-91253A292 1/4"-20 x 1 5/8" ASTM F835 Alloy Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with black-oxide coating, extending service life in demanding industrial environments
• Exceptional tensile strength of 130,000 psi ensures reliable performance under heavy loads and vibration
• Precise Class 3A thread fit provides secure engagement and reduces the risk of cross-threading during installation
• Hex drive design offers superior torque transmission and prevents tool slippage in high-torque applications
• Partially threaded shank allows for controlled clamping force and secure fastening in assembly operations
• 82° countersink angle enables flush mounting for clean, professional finishes in visible applications
• Full regulatory compliance with ASTM F835, RoHS 3, and REACH standards ensures environmental and safety adherence

Professional Applications & Engineering Value

Engineered for industrial fastening applications where reliability is paramount, these 1/4"-20 UNC flat head screws deliver exceptional performance in machinery assembly, equipment manufacturing, and structural frameworks. The black-oxide alloy steel construction provides superior protection against corrosion while maintaining Rockwell C39 hardness for wear resistance. The coarse UNC threading ensures quick installation and secure holding power, while the partially threaded design prevents over-tightening and material damage. Ideal for applications requiring flush mounting with their standard flat head profile, these screws solve critical challenges in vibration-prone environments where 130,000 psi tensile strength prevents fastener failure under dynamic loads.

Specification Summary & Compliance

These flat head screws feature precision 1/4"-20 UNC Class 3A threads with coarse spacing, manufactured to exacting dimensional standards. The inch system measurements ensure compatibility with North American equipment specifications, while the partially threaded shank maintains optimal engagement length. Compliance includes ASTM F835 specifications for mechanical properties, along with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental standards, ensuring safe use across various industrial sectors without hazardous substance restrictions.