S-92245A587 5/16"-18 x 1 1/2" FF-S-85, MS35307-338 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 and outdoor applications.
• High tensile strength of 70,000 psi ensures reliable load-bearing capacity and prevents fastener failure under stress.
• External hex drive and hex head design allows for easy installation and removal with standard tools, reducing assembly time.
• Class 2A thread fit provides consistent, reliable engagement for smooth assembly and disassembly without cross-threading.
• Partially threaded shank offers optimal clamping force distribution, minimizing material stress in precision assemblies.
• Coarse UNC threading enables quick installation and superior holding power in a wide range of materials.
• Compliance with Fed. Spec. FF-S-85 (MS35307-338), RoHS 3, and REACH guarantees adherence to strict industrial and environmental standards.

Professional Applications & Engineering Value

This 5/16"-18 UNC hex head screw is engineered to address critical challenges in industrial fastening, where corrosion resistance and mechanical reliability are paramount. The passivated 18-8 stainless steel material provides excellent protection against rust and chemical exposure, making it suitable for marine, chemical processing, and outdoor equipment applications. Its partially threaded design ensures that unthreaded sections bear directly against components, reducing the risk of loosening under vibration and improving joint integrity. With a coarse thread spacing and external hex drive, it allows for rapid installation in both soft and hard materials, streamlining assembly lines and maintenance operations. This screw delivers consistent performance in heavy-duty frameworks, machinery, and structural assemblies where 70,000 psi tensile strength and precise Class 2A thread fit prevent stripping and ensure long-term durability.

Specification Summary & Compliance

This fastener features a 5/16"-18 UNC coarse thread with Class 2A thread fit for standard tolerance and interchangeability. It complies with Fed. Spec. FF-S-85 (identified as MS35307-338) for dimensional and mechanical requirements, ensuring consistency in government and industrial contracts. Environmental and safety adherence is confirmed through RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) compliance, supporting sustainable and safe manufacturing practices. The Rockwell B74 hardness and specified thread dimensions (e.g., 1 1/2" length, 7/8" min thread length) further validate its reliability in demanding applications.