S-90429A133 3/8"-24 x 3 1/4" 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, reducing the risk of fastener failure.
• Class 3A thread fit provides superior precision and tight tolerances, minimizing backlash and improving assembly accuracy in critical setups.
• Black-oxide alloy steel construction offers enhanced corrosion resistance and durability, extending service life in harsh environments.
• Partially threaded design with UNF fine threads allows for secure fastening in materials requiring fine adjustment and vibration resistance.
• 82° countersink angle and flat head profile enable flush mounting, reducing protrusion and improving safety in compact assemblies.
• Hex drive (7/32") compatibility facilitates easy installation and removal with standard tools, saving time during maintenance.
• Compliance with ASME B18.3 and ASTM F835 standards ensures consistent quality and interoperability, meeting rigorous industry requirements.

Professional Applications & Engineering Value

This 3/8"-24 UNF flat head socket cap screw is engineered to address common industrial challenges, such as vibration loosening and material fatigue. Crafted from black-oxide alloy steel with a Rockwell C39 hardness, it withstands heavy loads and corrosive conditions, making it ideal for machinery, automotive, and aerospace applications. The partially threaded configuration and Class 3A thread fit provide precise engagement, reducing the need for re-tightening and enhancing joint integrity. Its 82° countersink ensures a seamless fit in pre-drilled holes, minimizing stress concentrations. By incorporating UNF fine threads, this screw offers superior holding power in dynamic environments, delivering long-term reliability for high-strength fastening solutions.

Specification Summary & Compliance

This screw adheres to Class 3A thread fit tolerances and UNF fine thread standards, ensuring dimensional accuracy and compatibility. It meets ASME B18.3 and ASTM F835 specifications for consistent manufacturing quality. Additionally, it is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, supporting environmentally responsible and safe usage in global markets.