S-90585A144 1/4"-20 x 9/16" ASME B18.3, ASTM F879 Stainless Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance thanks to 316 stainless steel construction and passivated finish, ideal for harsh environments and extended service life
• Exceptional mechanical strength with 70,000 psi tensile strength and Rockwell B55 hardness, ensuring reliable performance under high-stress loads
• Precision flush mounting enabled by the 82° countersink angle and flat head design, creating a smooth, secure surface finish
• High-reliability threading with Class 3A fit and UNC coarse thread profile, providing superior vibration resistance and easier assembly
• Optimized drive engagement from the 5/32" hex drive, allowing for high-torque installation and reducing the risk of stripping
• Full-length threading ensures maximum grip and holding power across the entire 9/16" length for robust fastening
• Comprehensive compliance with major industrial standards including ASME B18.3, RoHS 3, and REACH for guaranteed quality and safety

Professional Applications & Engineering Value

Engineered for demanding industrial applications, these 1/4"-20 UNC flat head screws solve critical challenges in machinery, marine, and chemical processing equipment. The 316 stainless steel material provides excellent resistance to chlorides and acidic environments, preventing premature failure. The combination of Class 3A thread fit and coarse threading ensures secure fastening in high-vibration settings, while the passivated finish enhances surface durability. The 82° countersink angle and flat head profile allow for seamless integration into precision assemblies, eliminating protrusions that could interfere with moving parts. These fully threaded hex drive screws deliver consistent clamping force across the entire engagement length, making them ideal for structural components, equipment panels, and heavy-duty enclosures where reliability is paramount.

Specification Summary & Compliance

This screw features precision 1/4"-20 UNC coarse threads with Class 3A fit for superior dimensional accuracy. Manufacturing complies with ASME B18.3 specifications ASTM F879, ensuring consistent quality and interchangeability. The product is fully RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant (06/14/2023 235 SVHC), meeting stringent environmental and safety regulations for industrial use worldwide.