S-91829A515 4-40 MS51575-3, NASM51575 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 Stainless Steel construction and passivated finish, ideal for harsh industrial environments
• Precise alignment and reduced wear due to the 1/8" shoulder diameter with tight tolerance (-0.001" to 0") for stable component positioning
• High mechanical strength offering 70,000 psi tensile strength and Rockwell B55 hardness for reliable performance under load
• Consistent thread engagement with UNC coarse threads and Class 2A fit, ensuring easy assembly and vibration resistance
• Secure drive mechanism featuring a socket head with slotted drive for high torque application and reduced stripping risk
• Regulatory compliance meeting MS51575-3, RoHS 3, and REACH standards for safe, environmentally responsible use
• Durable surface protection through passivation, enhancing longevity and maintaining integrity in demanding applications

Professional Applications & Engineering Value

This 4-40 UNC shoulder screw is engineered to address critical alignment and durability challenges in precision assemblies. The 18-8 Stainless Steel material, combined with a passivated finish, provides excellent resistance to corrosion and oxidation, making it suitable for industries like aerospace, electronics, and machinery where environmental factors are a concern. The 1/8" shoulder diameter with precise tolerances ensures accurate component positioning, reducing misalignment and wear in rotating parts or pivoting mechanisms. Its coarse UNC threads and Class 2A fit facilitate quick installation and reliable fastening, while the socket head design allows for high-torque applications without compromising integrity. Ideal for use in jigs, fixtures, and precision instruments, this shoulder screw delivers consistent performance, minimizing downtime and maintenance costs in industrial applications.

Specification Summary & Compliance

This shoulder screw adheres to Class 2A thread fit for standard UNC threads, ensuring dimensional accuracy and interchangeability. It meets MS51575-3 (NASM51575) specifications for quality and performance, with compliance to RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming it is free from hazardous substances and suitable for global industrial use.