S-91255A157 6-32 x 1 1/2" ASTM F835 Steel Button Head Hex-Drive Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with black-oxide coating, extending service life in demanding industrial environments
• Superior mechanical strength with 120,000 psi tensile strength and Rockwell C39 hardness for reliable performance under high stress
• Precision fastening ensured by Class 3A thread fit and UNC coarse threads for secure, vibration-resistant connections
• Easy installation and removal with 5/64" hex drive design, providing superior torque transmission compared to slotted drives
• Optimized load distribution through rounded button head profile, reducing surface damage while maintaining low-profile appearance
• Versatile partial threading allowing unthreaded shank sections to function as precision alignment pins or pivot points
• Regulatory compliance assurance meeting ASME B18.3, ASTM F835 standards plus RoHS 3 and REACH environmental regulations

Professional Applications & Engineering Value

This black-oxide alloy steel screw with 6-32 UNC coarse threading delivers exceptional performance in industrial assembly applications where vibration resistance and corrosion protection are critical. The partially threaded design provides dual functionality—the threaded portion ensures secure fastening while the smooth shank acts as a precision guide for alignment-sensitive applications. The rounded button head with hex drive offers superior torque transmission without protruding significantly, making it ideal for confined spaces in machinery, electronic enclosures, and automotive assemblies. The combination of 120,000 psi tensile strength and Rockwell C39 hardness ensures these industrial screws maintain integrity under dynamic loads, while the black-oxide surface treatment provides essential protection against oxidation in humid or chemically aggressive environments.

Specification Summary & Compliance

This 1-1/2" rounded head screw features precision Class 3A thread fit with 6-32 UNC coarse thread spacing and right-hand threading. Manufacturing complies with ASME B18.3 and ASTM F835 specifications, ensuring dimensional accuracy and performance reliability. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, meeting the latest standards for hazardous substance restrictions and chemical safety in industrial applications.