S-91253A727 1/2"-13 x 3 3/4" ASTM F835 Alloy Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 130,000 psi provides reliable performance in high-stress industrial applications
• Superior corrosion resistance from black-oxide coating extends service life in demanding environments
• Precision Class 3A thread fit ensures secure fastening with minimal vibration loosening
• Optimized 82° countersink angle allows for flush mounting and improved load distribution
• Hex drive design with 5/16" drive size enables high-torque installation without cam-out
• Partially threaded shank provides enhanced grip strength in joint applications
• Comprehensive compliance with ASTM F835, RoHS 3, and REACH ensures regulatory acceptance

Professional Applications & Engineering Value

Engineered for demanding industrial applications, these 1/2"-13 UNC flat head screws deliver exceptional performance where reliability is critical. The black-oxide alloy steel construction provides superior corrosion resistance while maintaining Rockwell C39 hardness for long-term durability. The coarse UNC threading combined with Class 3A thread fit ensures secure fastening in structural assemblies, machinery, and heavy equipment. The hex drive configuration allows for high-torque installation in confined spaces, making these partially threaded screws ideal for applications requiring precise clamp load control and vibration resistance in manufacturing, construction, and industrial maintenance environments.

Specification Summary & Compliance

This 3 3/4" flat head screw features precision Class 3A thread fit with 1/2"-13 UNC coarse threading and 82° countersink angle. Manufactured to ASTM F835 specifications with Rockwell C39 hardness and 130,000 psi tensile strength. Fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring safe use across global markets.