S-90337A387 4-40 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance thanks to 18-8 stainless steel construction and passivated finish, ideal for harsh industrial environments.
• Exceptional strength and durability with 70,000 psi tensile strength and Rockwell B55 hardness, ensuring reliable performance under high stress.
• Precise alignment and secure fit from the 1/8" shoulder diameter with tight tolerance and precise shoulder fit, minimizing assembly errors.
• Easy installation and removal with a low-profile hex socket head and 5/64" drive size, allowing efficient tool access in confined spaces.
• Wide compatibility and reliable threading due to UNC coarse threads and Class 2A fit, providing consistent engagement in various materials.
• Compliance with environmental standards including RoHS 3 and REACH, ensuring safe and sustainable use in global markets.
• Optimized for repetitive use with a smooth, low socket head profile that reduces wear and extends service life.

Professional Applications & Engineering Value

This 4-40 UNC shoulder screw is engineered to address common challenges in precision assemblies, such as misalignment and component wear. Made from 18-8 stainless steel with a passivated finish, it offers excellent resistance to corrosion and oxidation, making it suitable for applications in machinery, electronics, and automotive systems where exposure to moisture or chemicals is a concern. The 1/8" shoulder diameter with tight tolerances ensures accurate positioning of parts, while the 5/8" shoulder length provides stable support for rotating components like gears and pulleys. The coarse UNC threads and Class 2A fit facilitate quick installation and secure fastening, reducing assembly time and improving overall reliability in high-vibration environments. Ideal for use in jigs, fixtures, and precision instruments, this screw delivers consistent performance and long-term value.

Specification Summary & Compliance

This shoulder screw adheres to precise dimensional standards, including a Class 2A thread fit for consistent engagement and a shoulder diameter tolerance of -0.001" to 0" for exact alignment. It conforms to UNC thread specifications and is manufactured from 18-8 stainless steel with a passivated finish to enhance durability. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring it meets stringent environmental and safety requirements for industrial use.