S-97345A590 1/4"-28 ASME B18.3 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 316 stainless steel construction, ideal for harsh industrial and marine environments
• Precise component alignment ensured by the 3/8" diameter shoulder with tight tolerances for reduced assembly play
• High-strength performance delivering 70,000 psi tensile strength and 35,000 psi shear strength for demanding applications
• Secure, fine-thread engagement with Class 3A UNF 1/4"-28 threads for vibration resistance and reliable fastening
• Easy installation and removal using a standard 3/16" hex key drive and knurled head for improved grip
• Long-term reliability backed by Rockwell B79 hardness for excellent wear resistance and durability
• Regulatory compliance meeting ASME B18.3, RoHS 3, and REACH standards for global industrial use

Professional Applications & Engineering Value

This 316 stainless steel shoulder screw is engineered to solve critical alignment and corrosion challenges in precision assemblies. The 3/8" shoulder diameter with controlled tolerances provides a stable bearing surface for rotating parts, minimizing misalignment in machinery, pivots, and guides. The Class 3A UNF fine thread offers superior resistance to loosening under vibration, making it ideal for automotive, aerospace, and electronic equipment. With its knurled head and hex socket drive, installation is straightforward even in confined spaces. The corrosion-resistant material ensures longevity in aggressive environments, reducing maintenance frequency and downtime.

Specification Summary & Compliance

This shoulder screw features a 1/4"-28 UNF Class 3A fine thread with right-hand direction, ensuring high precision and fit. The shoulder diameter is 3/8" with a tolerance of -0.004" to -0.002", and the shoulder length is 3/4" with a tolerance of -0.005" to 0.005". It conforms to ASME B18.3 specifications and is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations.