S-97345A259 4-40 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 316 stainless steel construction, ideal for harsh or outdoor environments where rust prevention is critical.
• Exceptional mechanical strength offering 70,000 psi tensile and 35,000 psi shear strength for reliable performance in high-stress assemblies.
• Precise Class 3A thread fit ensures tight, secure mating with components, reducing the risk of loosening under vibration.
• Coarse 4-40 UNC threading enables faster installation and improved resistance to stripping compared to fine threads.
• Convenient hex socket drive allows for high-torque installation in confined spaces with standard tools.
• Long 2-inch shoulder provides accurate alignment and acts as a bearing surface or pivot in mechanical assemblies.
• Full environmental compliance with RoHS 3 and REACH standards, ensuring safety and suitability for regulated industries.

Professional Applications & Engineering Value

This 316 stainless steel shoulder screw is engineered to solve critical challenges in precision machinery and industrial equipment. The Class 3A thread fit and coarse 4-40 UNC threading deliver reliable fastening in high-vibration environments, preventing unintentional loosening. The 2-inch shoulder acts as a precise spacer or axle, maintaining component alignment in assemblies like rotating shafts, linkages, and bearing mounts. With a Rockwell B79 hardness and excellent corrosion resistance, it withstands aggressive chemicals and moisture, making it ideal for marine, chemical processing, and food-grade applications. The hex socket head facilitates secure installation in tight spaces, ensuring efficient maintenance and assembly for OEMs and MRO professionals.

Specification Summary & Compliance

This shoulder screw features a 4-40 UNC coarse thread with a precision Class 3A fit for secure fastening. The shoulder diameter is 1/8" with a tolerance of -0.004" to -0.002", and the shoulder length is 2" with a tolerance of -0.005" to 0.005". It is manufactured from 316 stainless steel with a tensile strength of 70,000 psi and a minimum shear strength of 35,000 psi. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations.