S-92245A912 1/4"-20 x 3 3/4" FF-S-85, MS35307-321 Mil. Spec. 18-8 Stainless Steel Hex Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with passivated 18-8 stainless steel construction, ideal for harsh environments and long-term outdoor use.
• Exceptional mechanical strength offering 70,000 psi tensile strength and Rockwell B74 hardness for reliable performance under high stress.
• Optimized load distribution through the partially threaded design, providing enhanced grip and stability in demanding assemblies.
• Precise and reliable fit with UNC coarse threads and Class 2A thread fit, ensuring easy installation and consistent engagement.
• Secure and efficient fastening enabled by the external hex drive and hex head, allowing for high torque application with standard tools.
• Compliance with rigorous standards including Fed. Spec. FF-S-85 (MS35307-321), ensuring quality and interoperability in regulated applications.
• Environmental and safety adherence with RoHS 3 and REACH compliance, supporting sustainable and safe manufacturing practices.

Professional Applications & Engineering Value

This 1/4"-20 x 3-3/4" partially threaded hex head screw is engineered to address critical challenges in industrial and structural applications. Made from passivated 18-8 stainless steel, it delivers outstanding corrosion resistance, making it suitable for marine, chemical, and outdoor settings where moisture and chemicals are prevalent. The UNC coarse threading and Class 2A fit provide quick assembly and reliable thread engagement, reducing installation time and minimizing the risk of cross-threading. With a high tensile strength of 70,000 psi and Rockwell B74 hardness, this screw withstands heavy loads and vibrations, ensuring long-term integrity in machinery, construction, and transportation equipment. Its partially threaded design concentrates clamping force where needed, enhancing joint stability and preventing loosening in dynamic environments.

Specification Summary & Compliance

This fastener adheres to precise dimensional and performance criteria, including a Class 2A thread fit for consistent accuracy and UNC coarse threads (1/4"-20) with a minimum thread length of 3/4". It meets Fed. Spec. FF-S-85 (MS35307-321) for quality assurance and is compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring it is free from hazardous substances and suitable for global markets.