S-90299A540 1/4"-20 x 3/4" ASME B18.3, ASTM A574 Brass-Tip Alloy Steel Socket Head Screws

Key Features & Benefits at a Glance

• Prevents surface damage with a nonmarring brass tip, ideal for delicate materials and finished surfaces.
• Superior corrosion resistance from the black-oxide finish on alloy steel, extending service life in demanding environments.
• Exceptional mechanical strength with a Rockwell C39 hardness and 180,000 psi tensile strength for high-stress applications.
• Precise and reliable fastening ensured by Class 3A thread fit and UNC coarse threads for easy assembly and vibration resistance.
• Secure hex drive engagement with a 3/16" drive size, providing high torque transmission and reducing tool slippage.
• Broad compliance with ASME B18.3, RoHS 3, and REACH standards, guaranteeing quality and environmental safety.
• Versatile fully threaded design for uniform clamping force and adaptability across various joint thicknesses.

Professional Applications & Engineering Value

This Black-Oxide Alloy Steel Socket Head Cap Screw is engineered to solve critical industrial fastening challenges. The nonmarring brass tip is essential for applications where surface integrity is paramount, such as in precision machinery, automotive assemblies, and electronic enclosures, preventing scratches and cosmetic damage. Its high tensile strength and Rockwell C39 hardness ensure it withstands heavy loads and dynamic stresses without failure, making it suitable for construction equipment, aerospace components, and heavy-duty manufacturing. The Class 3A UNC coarse thread facilitates quick installation and provides excellent resistance to loosening under vibration, reducing maintenance needs. Combined with a hex drive for secure tool engagement, this screw delivers reliable performance in demanding environments where durability and precision are non-negotiable.

Specification Summary & Compliance

This socket head cap screw adheres to precise dimensional standards, including a Class 3A thread fit for tight tolerances and UNC coarse threads (1/4"-20) per common industrial specifications. It is manufactured in compliance with ASME B18.3 and material standards such as ASTM A574, ensuring consistent quality and performance. Additionally, it meets regulatory requirements including RoHS 3 (2015/863/EU) and REACH (EC 1907/2006), confirming its safety for use in various markets without hazardous substances.