S-90585A537 1/4"-20 x 1/2" ASME B18.3 Stainless Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 316 stainless steel construction and passivated finish for extended service life in harsh environments
• Exceptional mechanical strength delivering 70,000 psi tensile strength and Rockwell B55 hardness for reliable performance under heavy loads
• Precision thread engagement with Class 3A fit and UNC coarse threads ensuring secure fastening and vibration resistance
• Optimized drive efficiency featuring 5/32" hex drive for high-torque installation without cam-out issues
• Flush mounting capability with standard 82° countersink angle flat head design for smooth surface finishes
• Full threading coverage along the 1/2" length provides maximum grip strength and adjustment flexibility
• Regulatory compliance assurance meeting ASME B18.3 standards and environmental regulations for industrial applications

Professional Applications & Engineering Value

These 1/4"-20 UNC flat head screws deliver critical performance advantages in demanding industrial settings where corrosion resistance and mechanical reliability are paramount. The 316 stainless steel composition combined with passivated finish provides exceptional protection against chemical exposure and atmospheric corrosion, making them ideal for marine equipment, chemical processing plants, and food processing machinery. The Class 3A thread fit with coarse thread spacing ensures rapid installation and maintains clamping force in high-vibration environments. The hex drive design allows for high-torque application without stripping, while the flat head profile creates seamless surface integration in countersunk applications. These engineering features collectively address common failure points in industrial fastening, providing long-term reliability and reduced maintenance costs.

Specification Summary & Compliance

Manufactured to precise dimensional standards with Class 3A thread fit tolerance and UNC thread form. The screws feature a head diameter of 0.531" with tolerance range of -0.051" to 0", head height of 0.161", and consistent 82° countersink angle. Full compliance with ASME B18.3 manufacturing specifications ensures dimensional accuracy and performance reliability. Environmental compliance includes RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming adherence to hazardous substance restrictions for global industrial applications.