S-90585A047 1/4"-28 x 1/4" ASME B18.3 Stainless Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 316 Stainless Steel construction and passivated finish for extended service life in harsh environments
• Precise thread engagement with Class 3A fit and UNF fine threading ensures reliable, vibration-resistant fastening
• High-strength performance delivering 70,000 psi tensile strength and Rockwell B55 hardness for demanding applications
• Optimal flush mounting with 82° countersink angle and undercut flat head design for seamless surface integration
• Efficient installation through 5/32" hex drive system providing secure tool engagement and torque transmission
• Full threading coverage across the entire 1/4" length maximizes grip strength and load distribution
• Regulatory compliance meeting ASME B18.3 standards, RoHS 3, and REACH for global industrial acceptance

Professional Applications & Engineering Value

These 316 Stainless Steel flat head screws address critical engineering challenges in corrosive and high-stress environments. The combination of UNF fine threading and Class 3A thread fit provides exceptional vibration resistance, making them ideal for precision machinery, marine equipment, and chemical processing applications where loosening under dynamic loads is a concern. The passivated finish enhances the natural corrosion resistance of 316 stainless steel, significantly extending service life in saltwater, chemical, and outdoor exposures. The undercut flat head profile with 82° countersink ensures perfect flush mounting while maximizing bearing surface, preventing material deformation in soft substrates. These features make them particularly valuable for aerospace components, medical devices, and food processing equipment where reliability, cleanliness, and regulatory compliance are paramount.

Specification Summary & Compliance

Manufactured to exacting inch system dimensions with Class 3A thread fit precision and UNF thread standard. The screws feature a right-hand thread direction with fully threaded 1/4" length and maintain strict compliance with ASME B18.3 manufacturing specifications. Environmental and safety certifications include full compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring they meet the latest international standards for hazardous substance restrictions and chemical safety.