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APPROVED VENDOR Key Locking Insert: Heavy Wall, 4 Keys, 5/16"-24 Int Thrd Sz, 1/2"-13 Ext Thrd Sz - Mil. Spec. Key-Locking Inserts
APPROVED VENDORMil. Spec. Key-Locking Inserts

APPROVED VENDOR Key Locking Insert: Heavy Wall, 4 Keys, 5/16"-24 Int Thrd Sz, 1/2"-13 Ext Thrd Sz

The APPROVED VENDOR Key Locking Insert is a heavy-wall, mil. spec. insert (MS51830-203) with 4 keys, 5/16"-24 internal thread, 1/2"-13 external thread, and 18-8 material. Supplied as a plain, 10-pack, it features…

SKU 3G-OTH-531794

Brand
APPROVED VENDOR
Item
Key Locking Insert: Heavy Wall, 4 Keys, 5/16"-24 Int Thrd Sz, 1/2"-13 Ext Thrd Sz
Category
Mil. Spec. Key-Locking Inserts
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Technical Specifications

APPROVED VENDOR
Manufacturer Part Number
217-076503
Type
Plain, 10 PK
Keys
4
Wall Type
Heavy Wall
Ext Thrd Sz
1/2"-13
Finish Type
Plain
Int Thrd Sz
5/16"-24
Thread Type
Coarse
Industry Standards
MS51830-203
Compatible Tap Size
1/2"-13
External Thread Fit
2A
Internal Thread Fit
3B
Material Grade/Class
18-8
System of Measurement
Inch
View Full Spec Sheet

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APPROVED VENDOR Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The APPROVED VENDOR Key Locking Insert is a heavy-wall, mil. spec. insert (MS51830-203) with 4 keys, 5/16"-24 internal thread, 1/2"-13 external thread, and 18-8 material. Supplied as a plain, 10-pack, it features coarse thread, 2A external fit, and 3B internal fit. 3G Electric interprets demand and delivers this genuine industrial insert across 14 departments, with specialist depth in combustion, pumps, and controls as an authorised distributor.

Frequently Asked Questions

What is a key locking insert used for?

A key locking insert repairs or reinforces stripped threads in metal assemblies, providing a durable, reusable thread. The APPROVED VENDOR heavy-wall insert with 4 keys locks into place to prevent rotation, ideal for aerospace, military, and industrial applications requiring MS51830-203 compliance.

What are the specifications of the APPROVED VENDOR key locking insert?

This heavy-wall insert has a 5/16"-24 internal thread and 1/2"-13 external thread, with 2A external and 3B internal fits. It is made of 18-8 stainless steel, plain finish, and meets MS51830-203. Supplied as a 10-pack, it includes 4 keys for secure locking.

Where to buy APPROVED VENDOR key locking inserts worldwide?

3G Electric supplies and delivers the APPROVED VENDOR key locking insert worldwide. As a global industrial solutions provider, we handle full logistics and customs clearance to ensure your order arrives at your facility, whether you are in North America, Europe, Asia, or elsewhere.

How to install a key locking insert?

Installation requires tapping the hole to the specified compatible tap size (1/2"-13), then driving the insert using a key locking insert tool until it is flush or slightly below the surface. The 4 keys expand into the parent material to lock the insert in place. Always follow the manufacturer's instructions for torque and depth.

Used in

Common applications for APPROVED VENDOR
Laboratory sampling — APPROVED VENDOR clear wide mouth glass bottles for collecting and storing liquid samples in non-sterile environments.
Steam heating maintenance — APPROVED VENDOR forged brass radiator valves for regulating steam flow in commercial building heating systems.
High-pressure cleaning — APPROVED VENDOR turbo spray nozzles for pressure washers used in industrial equipment cleaning up to 6,000 psi.
Cleanroom operations — APPROVED VENDOR vinyl task chairs for seating in ISO 5 classified manufacturing or assembly areas.
General sealing — APPROVED VENDOR natural rubber stoppers for closing laboratory flasks or test tubes in educational or research settings.
Tamper-evident security — APPROVED VENDOR brass lead and wire seals for securing utility meters, cargo containers, or access panels.

APPROVED VENDOR Products

3G Electric supplies APPROVED VENDOR mil. spec. key-locking inserts. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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