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APPROVED VENDOR Key Locking Insert: Thin Wall, 4 Keys, M8-1.00 Int Thrd Sz, M12x1.25 Ext Thrd Sz - Mil. Spec. Key-Locking Inserts
APPROVED VENDORMil. Spec. Key-Locking Inserts

APPROVED VENDOR Key Locking Insert: Thin Wall, 4 Keys, M8-1.00 Int Thrd Sz, M12x1.25 Ext Thrd Sz

The APPROVED VENDOR Key Locking Insert is a thin-wall, mil. spec. insert with 4 keys, M8-1.00 internal thread size, M12x1.25 external thread size, plain finish, and coarse thread type. It meets Fed Std. H28/21 and MJ…

SKU 3G-OTH-531778

Brand
APPROVED VENDOR
Item
Key Locking Insert: Thin Wall, 4 Keys, M8-1.00 Int Thrd Sz, M12x1.25 Ext Thrd Sz
Category
Mil. Spec. Key-Locking Inserts
Available to Order
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Technical Specifications

APPROVED VENDOR
Manufacturer Part Number
217-077553
Type
M8-1.00 Int Thrd Sz, M12x1.25 Ext Thrd Sz, Plain, 10 PK
Keys
4
Wall Type
Thin Wall
Finish Type
Plain
Thread Type
Coarse
Industry Standards
Fed Std. H28/21, MJ Form
Compatible Tap Size
M12x1.25
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 thin-wall, mil. spec. insert with 4 keys, M8-1.00 internal thread size, M12x1.25 external thread size, plain finish, and coarse thread type. It meets Fed Std. H28/21 and MJ Form standards, with 2A external and 3B internal thread fits, made from 18-8 material, and comes in a 10-pack (MPN 217-077553).

Frequently Asked Questions

What is an APPROVED VENDOR key locking insert used for?

This thin-wall key locking insert with 4 keys is used to repair or reinforce threaded holes in metal assemblies, especially where mil. spec. compliance is required. It meets Fed Std. H28/21 and MJ Form standards, making it suitable for aerospace, defense, and industrial applications needing reliable, vibration-resistant threads.

What are the specifications of the APPROVED VENDOR key locking insert 217-077553?

This insert has M8-1.00 internal thread and M12x1.25 external thread, with 2A external and 3B internal thread fits. It is made from 18-8 stainless steel, has a plain finish, coarse thread type, and comes in a 10-pack. It complies with Fed Std. H28/21 and MJ Form standards.

Where to buy APPROVED VENDOR key locking inserts worldwide?

3G Electric supplies APPROVED VENDOR key locking inserts worldwide. We handle full logistics, customs clearance, and delivery to your facility. Contact us for pricing and lead time on this M8-1.00 internal thread, M12x1.25 external thread, 10-pack insert (MPN 217-077553).

How to install a thin-wall key locking insert?

Installation requires tapping the hole to the compatible tap size (M12x1.25), then using a key locking insert tool to drive the insert until it is flush or slightly below the surface. The 4 keys lock into the parent material to prevent rotation. Follow standard mil. spec. installation procedures for best results.

Used in

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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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