S-91253A130 5-40 x 5/8" ASTM F835 Alloy Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with black-oxide coating for extended service life in demanding environments
• Superior tensile strength of 130,000 psi ensures reliable performance under high-stress applications
• Precision Class 3A thread fit provides secure fastening with minimal vibration loosening
• Hex drive design enables high-torque installation without cam-out issues
• 82° countersink angle allows for flush mounting in standard chamfered holes
• Full threading along the 5/8" length maximizes grip and load distribution
• Rockwell C39 hardness maintains structural integrity under repeated use

Professional Applications & Engineering Value

These 5-40 UNC flat head screws with black-oxide alloy steel construction address critical industrial fastening challenges where corrosion resistance and high tensile strength are paramount. The hex drive configuration prevents tool slippage during high-torque assembly in confined spaces, while the Class 3A thread fit ensures vibration-resistant connections in machinery, automotive components, and electrical enclosures. The fully threaded design with coarse thread spacing provides superior holding power in metallic substrates, making these industrial screws ideal for applications requiring reliable disassembly and reassembly cycles without thread degradation.

Specification Summary & Compliance

Manufactured to ASME B18.3 and ASTM F835 specifications with Class 3A thread fit precision. Compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations. Features UNC coarse threads with right-hand direction and 82° countersink angle in inch system measurements.