SEMS Screw: External Tooth, #4-40 Thread Size, 5/8 in Lg, Steel, Zinc-Plated
The SEMS Screw: External Tooth is a #4-40 thread size, 5/8 in length machine screw with an external tooth lock washer, made of steel with a zinc-plated finish, pan head, and Phillips drive (drive size #1). Supplied…
SKU 3G-OTH-528585
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Product Description
The SEMS Screw: External Tooth is a #4-40 thread size, 5/8 in length machine screw with an external tooth lock washer, made of steel with a zinc-plated finish, pan head, and Phillips drive (drive size #1). Supplied in a 100-piece pack (MPN MPPEI0-400620-100P), this OEM fastener is designed for applications requiring a pre-assembled locking washer to resist loosening under vibration.
Frequently Asked Questions
What is a SEMS screw with external tooth used for?
A SEMS screw with external tooth is used in industrial assembly where vibration resistance is critical. The pre-assembled lock washer bites into the mating surface to prevent loosening, making it ideal for machinery, panels, and electrical enclosures.
What are the specifications of the SEMS screw #4-40 x 5/8 in?
This SEMS screw has a #4-40 thread size, 5/8 in length, steel construction with zinc-plated finish, pan head, and Phillips drive (size #1). It includes an external tooth lock washer and comes in a 100-piece pack (MPN MPPEI0-400620-100P).
Where to buy SEMS screws #4-40 in worldwide?
3G Electric supplies SEMS screws #4-40 x 5/8 in to worldwide locations. As a global industrial solutions provider, we handle full logistics and customs clearance to deliver genuine SEMS fasteners to your facility, regardless of region.
How to select the right SEMS screw for vibration resistance?
Select a SEMS screw with an external tooth lock washer for applications subject to vibration. Match thread size (#4-40), length (5/8 in), and drive type (Phillips #1) to your assembly. The zinc-plated steel finish offers corrosion resistance in dry indoor environments.
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.









