S-91253A650 3/8"-16 x 5 1/2" ASTM F835 Alloy Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 130,000 psi ensures reliable performance in high-stress industrial applications.
• Superior corrosion resistance from the black-oxide finish extends service life in harsh environments.
• Precise Class 3A thread fit guarantees secure, vibration-resistant connections with minimal risk of loosening.
• High Rockwell C39 hardness provides excellent wear resistance and durability under repeated use.
• Partially threaded design allows for optimal clamping force and easier alignment in assembly.
• Standard 82° countersink angle enables flush mounting for a clean, professional finish.
• Hex drive compatibility with 7/32" tools facilitates quick installation and removal with standard equipment.

Professional Applications & Engineering Value

Engineered for demanding environments, these 3/8"-16 UNC flat head screws in black-oxide alloy steel address critical industrial challenges. The coarse thread spacing and Class 3A thread fit ensure rapid assembly and superior vibration resistance in heavy machinery, structural frameworks, and automotive components. With a Rockwell C39 hardness and 130,000 psi tensile strength, they withstand extreme loads and repetitive stress, reducing maintenance frequency. The black-oxide surface treatment combats corrosion in humid or chemical-exposed settings, while the partially threaded shank and 82° countersink enable precise, flush installations in metal, wood, and composite materials, streamlining production workflows.

Specification Summary & Compliance

This screw adheres to UNC thread standards with a Class 3A thread fit for high precision. It meets ASTM F835 manufacturing specifications and is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and material integrity.