SEMS Screw: External Tooth, #4-40 Thread Size, 3/8 in Lg, Stainless Steel, Passivated
The SEMS Screw: External Tooth is a #4-40 thread size, 3/8 in long, stainless steel, passivated, pan-head machine screw with an external tooth lock washer, supplied in a 50-pack (MPN 1-PPE-4C-37). It features a #1…
SKU 3G-OTH-528582
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Product Description
The SEMS Screw: External Tooth is a #4-40 thread size, 3/8 in long, stainless steel, passivated, pan-head machine screw with an external tooth lock washer, supplied in a 50-pack (MPN 1-PPE-4C-37). It features a #1 drive size, combining a fastener and washer in one assembly for efficient installation.
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 lock washer used for?
A SEMS screw with an external tooth lock washer is used to fasten components while resisting loosening from vibration. The pre-assembled washer saves installation time. Common in machinery, electrical enclosures, and panel assembly where a secure, corrosion-resistant stainless steel fastener is required.
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, stainless steel construction with passivated finish, pan head, and #1 drive size. It includes an external tooth lock washer pre-assembled. Supplied in a 50-pack under MPN 1-PPE-4C-37.
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 sourcing partner, we handle logistics, customs clearance, and delivery to your site. Contact us for pricing and lead time on this SEMS brand fastener.
How to install a SEMS screw with external tooth lock washer?
Install a SEMS screw by driving it with a #1 size driver into a pre-tapped hole or with a nut. The external tooth washer bites into the mating surface to resist loosening. Avoid over-torquing to prevent stripping the stainless steel threads. Use standard torque values for #4-40 fasteners.
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.









