S-92245A571 1/4"-28 x 1 1/2" FF-S-85, MS35308-312 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 industrial environments
• High tensile strength of 70,000 psi ensures reliable, long-lasting fastening under heavy loads
• Precise Class 2A thread fit guarantees smooth assembly and consistent engagement in UNF fine-thread applications
• Partially threaded design provides optimal grip and clamping force where full threading isn't required
• External hex drive with 7/16" head width allows for high-torque installation using standard tools
• Compliance with Fed. Spec. FF-S-85 (MS35308-312) ensures meeting rigorous government and industrial standards
• RoHS 3 and REACH compliant for environmentally responsible and safe usage in regulated industries

Professional Applications & Engineering Value

This 1/4"-28 UNF hex head screw delivers exceptional engineering value in demanding applications where corrosion resistance and mechanical reliability are critical. The passivated 18-8 stainless steel construction effectively combats oxidation and chemical exposure, making it ideal for marine, chemical processing, and outdoor equipment. The partial threading design concentrates clamping force precisely where needed, preventing joint loosening in vibrating environments. With Rockwell B74 hardness and 70,000 psi tensile strength, it maintains structural integrity in high-stress assemblies, while the UNF fine thread spacing ensures superior resistance to vibrational loosening compared to coarse threads. These characteristics make it particularly valuable in aerospace, military hardware, and precision machinery applications requiring Fed. Spec. FF-S-85 compliance.

Specification Summary & Compliance

This fastener features 1/4"-28 UNF right-hand threads with Class 2A fit for precision assembly, 1 1/2" length with 3/4" minimum thread length, and partial threading. Manufactured to meet Fed. Spec. FF-S-85 (MS35308-312) requirements and compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring both performance reliability and regulatory adherence for industrial applications.