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APPROVED VENDOR Key Locking Insert: Thin Wall, 4 Keys, M12x1.75 Int Thrd Sz, M16x1.5 Ext Thrd Sz - Mil. Spec. Key-Locking Inserts
APPROVED VENDORMil. Spec. Key-Locking Inserts

APPROVED VENDOR Key Locking Insert: Thin Wall, 4 Keys, M12x1.75 Int Thrd Sz, M16x1.5 Ext Thrd Sz

The APPROVED VENDOR Key Locking Insert is a thin-wall, mil-spec insert with 4 keys, M12x1.75 internal thread size, M16x1.5 external thread size, plain finish, and coarse thread type. It meets Fed Std. H28/21 and MJ…

SKU 3G-OTH-531705

Brand
APPROVED VENDOR
Item
Key Locking Insert: Thin Wall, 4 Keys, M12x1.75 Int Thrd Sz, M16x1.5 Ext Thrd Sz
Category
Mil. Spec. Key-Locking Inserts
Available to Order
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Technical Specifications

APPROVED VENDOR
Manufacturer Part Number
217-077356
Type
M12x1.75 Int Thrd Sz, M16x1.5 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
M16x1.5
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, M12x1.75 internal thread size, M16x1.5 external thread size, plain finish, and coarse thread type. It meets Fed Std. H28/21 and MJ Form standards, is made from 18-8 material, and comes in a 10-pack (MPN 217-077356).

Frequently Asked Questions

What is an APPROVED VENDOR key locking insert used for?

This thin-wall key locking insert repairs or reinforces stripped threads in metal assemblies, particularly in aerospace and defense applications. Its 4 keys lock the insert into place, preventing rotation under vibration. It meets Fed Std. H28/21 and MJ Form standards for mil-spec thread repair.

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

This thin-wall insert has M12x1.75 internal thread and M16x1.5 external thread, with 4 keys and a plain finish. It is made from 18-8 stainless steel, meets Fed Std. H28/21 and MJ Form standards, and comes in a 10-pack (MPN 217-077356). External thread fit is 2A; internal is 3B.

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. As a global industrial solutions provider, we source genuine mil-spec inserts like this 10-pack (MPN 217-077356) and support procurement across 14 industrial departments.

How to install a thin-wall key locking insert?

Installation requires tapping the hole to the specified compatible tap size (M16x1.5), then winding the insert onto a tangless installation tool. The 4 keys are set into the parent material using a key-setting tool to lock the insert. Always follow the manufacturer's torque and depth guidelines for mil-spec inserts.

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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