SEMS Screw: External Tooth, 1/4"-20 Thread Size, 1/2 in Lg, Steel, Zinc-Plated
The SEMS Screw: External Tooth is a machine screw with an integrated external tooth lock washer, supplied in a 50-pack. This steel, zinc-plated hex-head fastener has a 1/4"-20 thread size, 1/2 in length, and a 3/8 in…
SKU 3G-OTH-528606
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Product Description
The SEMS Screw: External Tooth is a machine screw with an integrated external tooth lock washer, supplied in a 50-pack. This steel, zinc-plated hex-head fastener has a 1/4"-20 thread size, 1/2 in length, and a 3/8 in drive size (MPN HTCEIF02500500US-050P).
Frequently Asked Questions
What is a SEMS external tooth screw used for?
A SEMS screw with an external tooth lock washer is used to fasten components while resisting loosening from vibration. The integrated washer bites into the mating surface, making it ideal for industrial assemblies in machinery, panels, and equipment where a secure, permanent hold is required.
What are the specifications of the SEMS screw 1/4-20 x 1/2 in?
This SEMS screw has a 1/4"-20 thread size, 1/2 in length, and a 3/8 in hex drive size. It is made of steel with a zinc-plated finish and includes an integrated external tooth lock washer. Supplied in a 50-pack, the manufacturer part number is HTCEIF02500500US-050P.
Where to buy SEMS external tooth screws worldwide?
3G Electric supplies SEMS external tooth screws worldwide, handling full logistics and customs clearance. As a global industrial sourcing partner, we provide genuine fasteners like this 1/4-20 x 1/2 in steel, zinc-plated hex-head screw with integrated lock washer. Contact us for availability and delivery to your location.
How to install a SEMS screw with external tooth lock washer?
Install a SEMS screw by driving it with a 3/8 in hex socket or wrench until the external tooth washer contacts the mating surface. Tighten to the recommended torque for a 1/4-20 steel fastener. The integrated washer eliminates the need for a separate lock washer, simplifying assembly and reducing parts handling.
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.









