S-91255A531 1/4"-20 x 3 1/2" ASTM F835 Steel Button Head Hex-Drive Screws

Key Features & Benefits at a Glance

• Exceptional durability with 120,000 psi tensile strength and Rockwell C39 hardness for reliable performance in demanding industrial environments
• Superior corrosion resistance thanks to the black-oxide finish on alloy steel, extending service life in various operating conditions
• Optimal torque transmission through the 5/32" hex drive design, ensuring secure installation and preventing tool slippage
• Precise thread engagement with Class 3A UNC coarse threads providing consistent, vibration-resistant fastening connections
• Full threading capability along the 3-1/2" length enables maximum grip range and adjustment flexibility in assemblies
• Rounded button head profile creates a low-profile, aesthetically clean finish while minimizing snag hazards
• Regulatory compliance assurance meeting ASME B18.3 and ASTM F835 standards for quality and performance reliability

Professional Applications & Engineering Value

These black-oxide alloy steel rounded head screws deliver critical performance advantages in industrial applications where vibration resistance, corrosion protection, and high tensile strength are paramount. The combination of Class 3A UNC coarse threading ensures rapid assembly with superior thread engagement, while the fully threaded design provides consistent clamping force across the entire fastener length. The 5/32" hex drive enables high-torque installation without cam-out, making these industrial screws ideal for machinery, heavy equipment, and structural assemblies where reliability cannot be compromised. The black-oxide surface treatment adds an extra layer of corrosion resistance, extending service life in challenging environments without sacrificing the material's inherent strength properties.

Specification Summary & Compliance

This 1/4"-20 x 3-1/2" rounded head screw features precision UNC coarse threads with Class 3A fit for optimal engagement and vibration resistance. Manufactured to exacting standards including ASME B18.3 and ASTM F835 specifications, ensuring dimensional accuracy and performance consistency. The fastener is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, making it suitable for global industrial applications with strict material requirements.