M8X1.25 Socket Head SEMS

M8X1.25 Socket Head SEMS with Split Lock Washer - Stainless

Stainless steel socket head SEMS screw with a pre-assembled captive split lock washer, combining the screw and washer into a single, efficient fastening solution. The SEMS design reduces part count, streamlines assembly, and minimizes the risk of dropped or lost washers—ideal for both manual and automated production environments.

The socket head features a low-profile cylindrical shape with an internal hex drive, perfect for assemblies with limited access or where external wrenching is not feasible. The split lock washer helps maintain clamping force by resisting loosening from vibration or thermal cycling, making this screw particularly effective in dynamic or high-vibration environments.

Length is measured from beneath the head, including the washer.

Material

Made from A2 stainless steel (equivalent to 304), this screw provides reliable corrosion resistance in most indoor and general outdoor environments. A2 offers a strong balance of durability, cost-effectiveness, and clean appearance.

However, A2 stainless is not suitable for marine or chemically aggressive or marine environments (for those, A4 (316) stainless would be a better choice). 

Use

Common in electronics, automation equipment, precision instruments, robotics, medical devices, and light industrial machinery, stainless steel socket head SEMS screws with captive washers are ideal where compact fastener heads and installation efficiency are critical.