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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-531801

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
Available to Order
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Technical Specifications

APPROVED VENDOR
Manufacturer Part Number
217-077363
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 a 2A external and 3B internal thread fit, compatible with M8x1.25 tap size, sold in a 10-pack (MPN 217-077363).

Frequently Asked Questions

What is an APPROVED VENDOR key locking insert used for?

This heavy-wall key locking insert with 4 keys is used to repair or reinforce threaded holes in metal assemblies, particularly in aerospace and defense applications. It meets Fed Std. H28/21 and MJ Form standards, ensuring reliable thread engagement for M4-0.70 internal and M8x1.25 external threads.

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

This insert has an M4-0.70 internal thread size and M8x1.25 external thread size, with a heavy wall, plain finish, and 18-8 material grade. It features 4 keys, a 2A external thread fit, 3B internal thread fit, and meets Fed Std. H28/21 and MJ Form standards. Sold in a 10-pack (MPN 217-077363).

Where to buy APPROVED VENDOR key locking inserts worldwide?

3G Electric supplies and delivers APPROVED VENDOR key locking inserts worldwide. As a global industrial solutions provider, we handle full logistics and customs clearance to ensure your order arrives at your facility. Contact us for availability and lead time on this 10-pack (MPN 217-077363).

How to install an APPROVED VENDOR key locking insert?

Installation requires tapping the hole to M8x1.25, then using a compatible installation tool to drive the insert until the keys engage. Ensure the external thread fit is 2A and internal fit is 3B for proper locking. Follow standard mil-spec practices for key locking inserts to avoid cross-threading.

Used in

Common applications for APPROVED VENDOR
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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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