S-91273A371 M4 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 Stainless Steel construction, ideal for harsh industrial environments and outdoor applications.
• Exceptional mechanical strength offering 70,000 psi tensile strength and 35,000 psi minimum shear strength for reliable, high-stress load-bearing.
• Precise assembly and alignment enabled by the 18mm shoulder length with tight tolerances, ensuring accurate component positioning.
• Secure, non-slip fastening thanks to the knurled head texture and hex socket drive, providing excellent grip during installation.
• Wide compatibility and easy installation with a standard M4 x 0.7mm coarse metric thread and Class 5g6g fit, suitable for common industrial equipment.
• Durable, long-lasting performance backed by Rockwell B55 hardness, resisting wear and deformation over repeated use.
• Compliance with global environmental standards including RoHS 3 and REACH, ensuring safe and sustainable use in regulated industries.

Professional Applications & Engineering Value

This M4 shoulder screw is engineered to address critical challenges in precision assembly and machinery. The 18-8 Stainless Steel material provides excellent resistance to rust and corrosion, making it suitable for applications in moist or chemically aggressive environments, such as food processing, marine equipment, and automotive systems. The hex socket drive and knurled head ensure secure tool engagement, reducing the risk of stripping and enabling efficient installation in confined spaces. The 18mm shoulder length with precise tolerances acts as a pivot or spacer, maintaining exact alignment between components and minimizing misalignment issues in rotating assemblies, jigs, and fixtures. This design enhances operational reliability, reduces maintenance downtime, and supports high-performance requirements in industrial automation and precision engineering.

Specification Summary & Compliance

The screw features a Class 5g6g thread fit per metric standards, ensuring consistent engagement and interchangeability. Shoulder diameter tolerance is -0.04 to -0.01 mm, and shoulder length tolerance is 0 to 0.25 mm, providing high dimensional accuracy. It complies with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming adherence to environmental and safety standards for industrial fasteners.