SEMS Screw: External Tooth, #4-40 Thread Size, 3/8 in Lg, Steel, Zinc-Plated
The SEMS Screw: External Tooth is a #4-40 thread size, 3/8 in length machine screw with an external tooth lock washer, made of steel with zinc plating, pan head, Phillips drive, and a #1 drive size. Supplied in a…
SKU 3G-OTH-528581
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Product Description
The SEMS Screw: External Tooth is a #4-40 thread size, 3/8 in length machine screw with an external tooth lock washer, made of steel with zinc plating, pan head, Phillips drive, and a #1 drive size. Supplied in a 100-piece pack (MPN MPPEI0-400370-100P), this OEM part is a standard fastener for industrial assembly applications.
Supplied to the Philippines — compatible with 60 Hz installations. DHL Express delivery to Manila, Quezon City, Cebu, customs and duties handled door-to-door.
Frequently Asked Questions
What is a SEMS screw with external tooth used for?
A SEMS screw with an external tooth lock washer is used in industrial assembly to fasten components while resisting loosening from vibration. The pre-assembled washer eliminates separate handling, making it ideal for high-volume production in machinery, electrical enclosures, and automotive applications.
What are the specifications of the SEMS screw #4-40 x 3/8 in?
This SEMS screw has a #4-40 thread size, 3/8 in length, steel construction with zinc plating, pan head, Phillips drive, and #1 drive size. It includes an external tooth lock washer and comes in a 100-piece pack (MPN MPPEI0-400370-100P).
Where to buy SEMS screws #4-40 x 3/8 in worldwide?
3G Electric supplies SEMS screws #4-40 x 3/8 in worldwide. As a global industrial solutions provider, we handle full logistics and customs clearance to deliver this OEM fastener to your facility. Contact us for availability and lead time.
How to select the correct SEMS screw for assembly?
Select a SEMS screw by matching thread size, length, head type, and drive style to your application. For vibration-prone assemblies, the external tooth lock washer provides grip. Ensure material compatibility—zinc-plated steel suits indoor use. Verify drive size matches your tooling.
SEMS Products
3G Electric supplies SEMS machine screws with external tooth lock washers. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.









