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APPROVED VENDOR Key Locking Insert: Thin Wall, 2 Keys, M2-0.40 Int Thrd Sz, M4-0.70 Ext Thrd Sz - Mil. Spec. Key-Locking Inserts
APPROVED VENDORMil. Spec. Key-Locking Inserts

APPROVED VENDOR Key Locking Insert: Thin Wall, 2 Keys, M2-0.40 Int Thrd Sz, M4-0.70 Ext Thrd Sz

The APPROVED VENDOR Key Locking Insert is a thin-wall, metric mil-spec insert with 2 keys, M2-0.40 internal thread size, M4-0.70 external thread size, plain finish, and 18-8 material grade. It meets Fed Std. H28/21…

SKU 3G-OTH-531683

Brand
APPROVED VENDOR
Item
Key Locking Insert: Thin Wall, 2 Keys, M2-0.40 Int Thrd Sz, M4-0.70 Ext Thrd Sz
Category
Mil. Spec. Key-Locking Inserts
Available to Order
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Technical Specifications

APPROVED VENDOR
Manufacturer Part Number
217-077382
Type
M2-0.40 Int Thrd Sz, M4-0.70 Ext Thrd Sz, Plain, 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
M4-0.70
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, metric mil-spec insert with 2 keys, M2-0.40 internal thread size, M4-0.70 external thread size, plain finish, and 18-8 material grade. It meets Fed Std. H28/21 and MJ Form standards, with external thread fit 2A and internal thread fit 3B, compatible with M4-0.70 tap size, supplied in a 10-pack (MPN 217-077382).

Frequently Asked Questions

What is a key locking insert used for?

A key locking insert repairs or reinforces tapped threads in soft materials like aluminum. The APPROVED VENDOR thin-wall insert with 2 keys locks into place to prevent rotation, providing strong, reusable metric threads (M2-0.40 internal, M4-0.70 external) in aerospace, defense, and industrial assemblies.

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

This thin-wall insert has M2-0.40 internal thread size, M4-0.70 external thread size, 2 keys, plain finish, 18-8 material grade, external thread fit 2A, internal thread fit 3B, and meets Fed Std. H28/21 and MJ Form standards. Compatible tap size is M4-0.70. Supplied in a 10-pack (MPN 217-077382).

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, customs clearance, and delivery to your facility. Contact us to order the 10-pack (MPN 217-077382) or other mil-spec inserts for your application.

How to install a key locking insert?

Installation requires drilling to the specified tap size (M4-0.70), tapping the hole, then threading the insert using a compatible installation tool. The 2 keys lock into the parent material to prevent rotation. Use a tang break-off tool if needed. Follow standard mil-spec practices for thread repair and reinforcement.

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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