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APPROVED VENDOR Key Locking Insert: Thin Wall, 2 Keys, M2.5-0.45 Int Thrd Sz, M4.5-0.75 Ext Thrd Sz - Mil. Spec. Key-Locking Inserts
APPROVED VENDORMil. Spec. Key-Locking Inserts

APPROVED VENDOR Key Locking Insert: Thin Wall, 2 Keys, M2.5-0.45 Int Thrd Sz, M4.5-0.75 Ext Thrd Sz

The APPROVED VENDOR Key Locking Insert is a thin-wall, mil. spec. insert with M2.5-0.45 internal and M4.5-0.75 external thread sizes, supplied in a 10-pack. It features 2 keys, a plain finish, coarse thread type, and…

SKU 3G-OTH-531783

Brand
APPROVED VENDOR
Item
Key Locking Insert: Thin Wall, 2 Keys, M2.5-0.45 Int Thrd Sz, M4.5-0.75 Ext Thrd Sz
Category
Mil. Spec. Key-Locking Inserts
Available to Order
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Technical Specifications

APPROVED VENDOR
Manufacturer Part Number
217-077383
Type
M2.5-0.45 Int Thrd Sz, M4.5-0.75 Ext Thrd Sz, Plain, 10 PK
Keys
2
Wall Type
Thin Wall
Finish Type
Plain
Thread Type
Coarse
Industry Standards
Fed Std. H28/21, MJ Form
Compatible Tap Size
M4.5-0.75
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 M2.5-0.45 internal and M4.5-0.75 external thread sizes, supplied in a 10-pack. It features 2 keys, a plain finish, coarse thread type, and is made from 18-8 material, meeting Fed Std. H28/21 and MJ Form standards. Compatible with M4.5-0.75 tap size, it has external thread fit 2A and internal thread fit 3B.

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 where high-strength or mil. spec. compliance is required. The APPROVED VENDOR thin-wall insert with M2.5-0.45 internal thread and two keys provides a permanent, vibration-resistant thread in aerospace, defense, and industrial applications.

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

This thin-wall insert has M2.5-0.45 internal and M4.5-0.75 external threads, 18-8 material, plain finish, and two keys. It meets Fed Std. H28/21 and MJ Form standards, with external thread fit 2A and internal thread fit 3B. Supplied in a 10-pack, it is compatible with M4.5-0.75 tap size.

Where to buy APPROVED VENDOR key locking inserts worldwide?

3G Electric supplies APPROVED VENDOR key locking inserts worldwide. As a global industrial solutions provider, we handle full logistics and customs clearance to deliver these mil. spec. inserts to your facility. Contact us for pricing and lead time on the 10-pack (MPN 217-077383).

How to install a key locking insert?

Installation requires tapping the hole to the specified compatible tap size (M4.5-0.75), then driving the insert using a proper installation tool until the keys engage. Ensure the insert is flush or slightly below the surface. Use a locking tool to set the keys into the parent material for a secure, vibration-resistant thread.

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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