S-91273A434 M8 Shoulder Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 18-8 stainless steel construction, ideal for harsh industrial environments and washdown applications.
• Enhanced assembly precision and component alignment thanks to the 40mm shoulder with controlled diameter tolerance for accurate positioning.
• High mechanical strength and durability with a tensile strength of 70,000 psi and Rockwell B55 hardness for reliable performance under load.
• Secure, non-slip installation provided by the knurled head and 4mm hex socket drive, allowing for high-torque application.
• Wide compatibility and easy installation with a coarse M8x1.25 thread (Class 5g6g fit) that resists cross-threading and speeds up assembly.
• Compliance with strict environmental regulations, being RoHS 3 and REACH compliant for use in regulated markets and eco-conscious projects.
• Reliable shear strength of 35,000 psi minimum, ensuring joint integrity in dynamic or vibrating assemblies.

Professional Applications & Engineering Value

This M8 shoulder screw is engineered to solve critical alignment and pivot point challenges in precision assemblies. The 40mm shoulder length acts as a precise shaft for locating gears, bearings, or linkages, eliminating the need for additional bushings and reducing assembly complexity. Manufactured from 18-8 stainless steel, it provides excellent resistance to rust and corrosion, making it suitable for food processing, packaging machinery, and outdoor equipment. The coarse metric thread (M8x1.25) and Class 5g6g thread fit ensure rapid, secure fastening with a reduced risk of stripping. The combination of a knurled head and hex socket drive offers superior grip and torque transmission, which is vital in automated production lines where tool slippage can cause downtime. This socket head shoulder screw delivers lasting performance and simplifies design in demanding mechanical systems.

Specification Summary & Compliance

This precision metric shoulder screw features an M8x1.25 coarse thread with a Class 5g6g thread fit and a 13mm thread length. The shoulder diameter is 8 mm with a tolerance of -0.04 to -0.01 mm, and the shoulder length is 40 mm with a tolerance of 0 to 0.25 mm, ensuring high dimensional accuracy. It is manufactured from 18-8 Stainless Steel with a hardness of Rockwell B55, 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) regulations.