S-90337A384 4-40 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 Stainless Steel construction, ideal for harsh environments and washdown applications.
• Precise component alignment ensured by the smooth, accurately machined shoulder with a tight diameter tolerance of -0.001" to 0".
• High-strength performance with a tensile strength of 70,000 psi and Rockwell B55 hardness for reliable load-bearing in demanding assemblies.
• Space-saving low-profile head allows for use in compact designs while providing secure engagement with a 5/64" hex drive.
• Consistent and reliable threading with a Class 2A fit on the 4-40 UNC coarse thread, ensuring easy assembly and vibration resistance.
• Environmental regulation compliance meets RoHS 3 and REACH standards, making it suitable for global markets and sensitive applications.
• Optimized for right-hand thread applications in machinery, fixtures, and pivots where standard directional fastening is required.

Professional Applications & Engineering Value

This low profile socket head shoulder screw is engineered to address critical alignment and pivot point challenges in precision assemblies. The 1-1/8" shoulder length provides a stable, unthreaded bearing surface that maintains exact part positioning, reducing wear and misalignment in rotating components like gears, linkages, and optical mounts. Manufactured from 18-8 Stainless Steel, it offers excellent corrosion resistance for use in medical devices, food processing equipment, and outdoor machinery. The 4-40 UNC coarse thread and Class 2A fit facilitate quick installation with standard hex tools, while the smooth shoulder diameter ensures minimal clearance for high-accuracy applications. Its robust 70,000 psi tensile strength supports dynamic loads, making it a reliable choice for industrial automation, aerospace fixtures, and electronic enclosures where durability and precision are paramount.

Specification Summary & Compliance

This shoulder screw adheres to UNC thread standards with a Class 2A thread fit for consistent engagement. The shoulder features precise dimensions: diameter of 1/8" with a tolerance of -0.001" to 0", and length of 1-1/8" with a tolerance of 0" to 0.002". It is manufactured to meet RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) compliance, ensuring it is free of restricted hazardous substances and suitable for international industrial use.