S-91306A281 1/4"-20 x 1 3/4" ASTM F835 Steel Button Head Hex-Drive Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with zinc plating that protects against rust and extends service life in harsh industrial environments
• High-strength construction delivers 120,000 PSI tensile strength and Rockwell C39 hardness for reliable performance under heavy loads
• Precise Class 3A thread fit ensures tight, secure fastening with minimal risk of loosening in vibration-prone applications
• Easy installation and removal with 5/32" hex drive that provides excellent torque transmission and reduces tool slippage
• Full threading design allows maximum grip length and uniform stress distribution across the entire fastener
• Standard UNC coarse threads enable quick assembly and disassembly while resisting cross-threading during installation
• Compliant with major industry standards including ASME B18.3 and ASTM F835 for guaranteed quality and interoperability

Professional Applications & Engineering Value

This zinc-plated alloy steel rounded head screw addresses critical engineering challenges in industrial assembly where vibration resistance and corrosion protection are paramount. The combination of 120,000 PSI tensile strength and Class 3A thread fit ensures reliable performance in heavy machinery, automotive components, and structural frameworks where loosening under dynamic loads can cause equipment failure. The button head profile provides a low-profile finish that minimizes snagging while the fully threaded UNC coarse design accelerates assembly in production environments. The zinc plating offers essential protection against moisture and chemicals, making these hex drive screws ideal for outdoor equipment, manufacturing fixtures, and maintenance applications requiring durable, long-lasting fasteners.

Specification Summary & Compliance

This fastener features precision 1/4"-20 UNC coarse threads with Class 3A thread fit for superior dimensional accuracy. Manufacturing complies with ASME B18.3 and ASTM F835 specifications, ensuring consistent quality and performance. The product is fully RoHS 3 (2015/863/EU) compliant and REACH (EC 1907/2006) compliant, meeting the latest environmental regulations for industrial components. With Rockwell C39 hardness and verified 120,000 PSI tensile strength, this screw delivers reliable mechanical properties for demanding applications.