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APPROVED VENDOR Key Locking Insert: Heavy Wall, 4 Keys, 3/8"-24 Int Thrd Sz, 9/16"-12 Ext Thrd Sz - Mil. Spec. Key-Locking Inserts
APPROVED VENDORMil. Spec. Key-Locking Inserts

APPROVED VENDOR Key Locking Insert: Heavy Wall, 4 Keys, 3/8"-24 Int Thrd Sz, 9/16"-12 Ext Thrd Sz

The APPROVED VENDOR Key Locking Insert is a Mil. Spec. heavy-wall insert with 4 keys, 3/8"-24 internal thread size, and 9/16"-12 external thread size. It meets MS51831-105L standards, is made of 18-8 material, and…

SKU 3G-OTH-531647

Brand
APPROVED VENDOR
Item
Key Locking Insert: Heavy Wall, 4 Keys, 3/8"-24 Int Thrd Sz, 9/16"-12 Ext Thrd Sz
Category
Mil. Spec. Key-Locking Inserts
Available to Order
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Technical Specifications

APPROVED VENDOR
Manufacturer Part Number
217-077504
Type
Plain, 10 PK
Keys
4
Wall Type
Heavy Wall
Ext Thrd Sz
9/16"-12
Finish Type
Plain
Int Thrd Sz
3/8"-24
Thread Type
Coarse
Industry Standards
MS51831-105L
Compatible Tap Size
9/16"-12
External Thread Fit
2A
Internal Thread Fit
3B
Material Grade/Class
18-8
System of Measurement
Inch
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APPROVED VENDOR Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The APPROVED VENDOR Key Locking Insert is a Mil. Spec. heavy-wall insert with 4 keys, 3/8"-24 internal thread size, and 9/16"-12 external thread size. It meets MS51831-105L standards, is made of 18-8 material, and comes in a plain finish, 10 PK.

Frequently Asked Questions

What is a key locking insert used for?

A key locking insert is used to repair or reinforce tapped threads in metal assemblies, especially in aerospace, defense, and industrial applications. The APPROVED VENDOR heavy-wall insert with 4 keys provides a permanent thread that resists loosening under vibration, meeting Mil. Spec. MS51831-105L standards.

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

This heavy-wall insert has a 3/8"-24 internal thread size and a 9/16"-12 external thread size, with 4 keys and a plain finish. It is made of 18-8 material, meets MS51831-105L standards, and comes in a 10 PK. External thread fit is 2A; internal thread fit is 3B.

Where to buy APPROVED VENDOR key locking inserts worldwide?

3G Electric supplies the APPROVED VENDOR key locking insert (MPN 217-077504) to customers worldwide. We handle full logistics, customs clearance, and delivery for global orders, ensuring you receive genuine Mil. Spec. inserts that meet MS51831-105L standards.

How to install a key locking insert?

Installation requires drilling to the compatible tap size (9/16"-12), tapping the hole, then driving the insert using a key locking insert tool until it sits below the surface. The 4 keys are then set 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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