S-91273A771 M3 Shoulder Screws

Key Features & Benefits at a Glance

• Corrosion-resistant performance with 18-8 stainless steel construction and black oxide finish, ideal for humid or chemically exposed environments.
• Precise alignment and secure component positioning thanks to the 4mm shoulder length with controlled tolerances, reducing assembly errors.
• High mechanical strength delivering 70,000 psi tensile and 35,000 psi shear strength for reliable load-bearing in dynamic applications.
• Easy installation and removal with a knurled socket head and 2mm hex drive, preventing tool slippage under torque.
• Consistent thread engagement ensured by Class 5g6g metric coarse thread fit, minimizing cross-threading risks.
• Durable surface protection from the black oxide coating, enhancing wear resistance and extending service life.
• Compliance with international regulations including RoHS 3 and REACH, ensuring safety and environmental standards are met.

Professional Applications & Engineering Value

This M3 shoulder screw is engineered to address common industrial challenges such as misalignment, vibration loosening, and corrosion in precision assemblies. The 18-8 stainless steel material provides excellent resistance to rust and oxidation, while the black oxide finish adds an extra layer of durability against abrasion. The 4mm shoulder length acts as a precise spacer or pivot in machinery, ensuring components like gears, bearings, or linkages maintain exact positioning without additional bushings. With a coarse thread pitch of 0.5mm and Class 5g6g thread fit, it offers quick assembly and reliable holding power in automated equipment, electronic enclosures, and automotive subsystems. The knurled socket head design enhances grip during manual or automated driving, reducing installation time and improving workflow efficiency in high-volume production settings.

Specification Summary & Compliance

This shoulder screw adheres to metric system standards with an M3x0.5mm coarse thread and Class 5g6g thread fit for consistent dimensional accuracy. The shoulder diameter tolerance is -0.04 to -0.01 mm, and shoulder length tolerance is 0 to 0.25 mm, ensuring precise fits in mating parts. It complies with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming the absence of hazardous substances. Manufactured to deliver 70,000 psi tensile strength and Rockwell B55 hardness, it meets rigorous industrial demands for durability and performance.