S-90283A108 4-40 x 3/8" ASME B18.6.3 Steel Pan Head Slotted Screws

Key Features & Benefits at a Glance

• Enhanced corrosion resistance through zinc plating, extending service life in demanding industrial environments
• Superior holding power with 60,000 psi tensile strength for reliable fastening in high-stress applications
• Optimized thread engagement with Class 2A coarse UNC threads ensuring secure installation and vibration resistance
• Easy manual installation featuring a standard slotted drive compatible with common screwdrivers
• Reduced surface damage from the rounded pan head design that minimizes marring on contact surfaces
• Full threading coverage along the 3/8" length provides maximum grip strength across the entire fastener
• Regulatory compliance assurance meeting ASME B18.6.3, RoHS 3, and REACH standards for global industrial use

Professional Applications & Engineering Value

These 4-40 UNC zinc-plated steel screws deliver exceptional performance in industrial machinery, electronic enclosures, and precision equipment assemblies. The coarse thread design ensures rapid installation and superior resistance to vibration loosening, while the Rockwell B60 hardness provides optimal balance between strength and machinability. The fully threaded configuration maximizes contact surface area, distributing load evenly to prevent joint failure. The rounded pan head with slotted drive offers both aesthetic appeal and practical installation benefits, making these industrial screws ideal for applications requiring both structural integrity and visual cleanliness in manufacturing environments.

Specification Summary & Compliance

Manufactured to precise Class 2A thread fit tolerances with UNC coarse threading (4-40 size) and 0.219" head diameter. Complies with ASME B18.6.3 manufacturing specifications and maintains full compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations. The 3/8" length and fully threaded design ensure consistent performance across industrial applications.