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APPROVED VENDOR Key Locking Insert: Heavy Wall, 4 Keys, M4-0.70 Int Thrd Sz, M8x1.25 Ext Thrd Sz - Mil. Spec. Key-Locking Inserts
APPROVED VENDORMil. Spec. Key-Locking Inserts

APPROVED VENDOR Key Locking Insert: Heavy Wall, 4 Keys, M4-0.70 Int Thrd Sz, M8x1.25 Ext Thrd Sz

The APPROVED VENDOR Key Locking Insert is a heavy-wall, mil. spec. insert with 4 keys, M4-0.70 internal thread size, M8x1.25 external thread size, plain finish, and 18-8 material. It meets Fed Std. H28/21 and MJ Form…

SKU 3G-OTH-531685

Brand
APPROVED VENDOR
Item
Key Locking Insert: Heavy Wall, 4 Keys, M4-0.70 Int Thrd Sz, M8x1.25 Ext Thrd Sz
Category
Mil. Spec. Key-Locking Inserts
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Technical Specifications

APPROVED VENDOR
Manufacturer Part Number
217-076363
Type
M4-0.70 Int Thrd Sz, M8x1.25 Ext Thrd Sz, Plain, 10 PK
Keys
4
Wall Type
Heavy Wall
Finish Type
Plain
Thread Type
Coarse
Industry Standards
Fed Std. H28/21, MJ Form
Compatible Tap Size
M8x1.25
External Thread Fit
2A
Internal Thread Fit
3B
Material Grade/Class
18-8
System of Measurement
Metric
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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 with 4 keys, M4-0.70 internal thread size, M8x1.25 external thread size, plain finish, and 18-8 material. It meets Fed Std. H28/21 and MJ Form standards, with 2A external and 3B internal thread fits, compatible with M8x1.25 tap size, sold in a 10-pack (MPN 217-076363).

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, providing a strong, reusable thread in softer materials. The APPROVED VENDOR heavy-wall insert with 4 keys meets mil. spec. Fed Std. H28/21 and MJ Form standards, making it suitable for aerospace, defense, and industrial applications requiring high reliability.

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

This heavy-wall insert has M4-0.70 internal thread size and M8x1.25 external thread size, with 2A external and 3B internal thread fits. It is made from 18-8 stainless steel, plain finish, compatible with M8x1.25 tap size, and meets Fed Std. H28/21 and MJ Form standards. Sold in a 10-pack (MPN 217-076363).

Where to buy APPROVED VENDOR key locking inserts worldwide?

3G Electric supplies APPROVED VENDOR key locking inserts worldwide, handling full logistics and customs clearance for global delivery. As a sourcing partner across 14 industrial departments, we provide these mil. spec. inserts with 4 keys, M4-0.70 internal thread, and M8x1.25 external thread, ensuring compliance with Fed Std. H28/21 and MJ Form standards.

How to install a key locking insert?

To install, drill and tap the hole to the specified compatible tap size (M8x1.25), then use a key locking insert tool to wind the insert into the tapped hole until the keys engage. The 4 keys lock the insert in place, preventing rotation. Follow standard thread repair practices and torque specifications for 18-8 stainless steel inserts.

Used in

Common applications for APPROVED VENDOR
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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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