S-90400A215 4-40 x 3/8" ASME B18.13 Steel Pan Head Phillips Screws with Spring Lock Washer

Key Features & Benefits at a Glance

• Enhanced corrosion resistance through zinc-plated steel construction, extending service life in demanding industrial environments
• Superior vibration resistance with integrated spring lock washer that maintains clamp force and prevents loosening under dynamic loads
• High-strength performance with 60,000 psi tensile strength and Rockwell B70 hardness for reliable fastening in critical applications
• Optimized drive engagement with Phillips No. 1 drive style providing efficient installation and reduced cam-out risk
• Full-thread design ensures maximum grip length and uniform stress distribution along the entire fastener length
• Precision thread fit with Class 2A UNC coarse threads enabling quick assembly and reliable engagement in various materials
• Comprehensive compliance meeting ASME B18.13 specifications and environmental standards including RoHS 3 and REACH

Professional Applications & Engineering Value

These zinc-plated steel rounded head screws with integrated spring lock washers deliver exceptional engineering value across industrial applications where vibration resistance and reliable fastening are critical. The combination of 4-40 UNC coarse threading and Class 2A thread fit ensures rapid assembly in metal, plastic, and composite materials while maintaining precise tolerances. The pan head profile with Phillips No. 1 drive provides optimal bearing surface and torque transmission, making these screws ideal for electronic enclosures, machinery panels, and automotive components where space constraints and vibration challenges exist. The fully threaded design maximizes thread engagement in both thick and thin materials, while the zinc plating offers corrosion protection for extended service life in various operating environments.

Specification Summary & Compliance

This fastener features precision 4-40 UNC coarse threads with Class 2A thread fit tolerances and right-hand threading. Manufacturing complies with ASME B18.13 specifications, ensuring dimensional accuracy and performance reliability. The product meets RoHS 3 (2015/863/EU) compliance for restricted substances and REACH (EC 1907/2006) environmental standards, confirming suitability for global industrial applications requiring strict regulatory adherence.