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APPROVED VENDOR Key Locking Insert: Heavy Wall, 4 Keys, M12x1.25 Int Thrd Sz, M18-1.50 Ext Thrd Sz - Mil. Spec. Key-Locking Inserts
APPROVED VENDORMil. Spec. Key-Locking Inserts

APPROVED VENDOR Key Locking Insert: Heavy Wall, 4 Keys, M12x1.25 Int Thrd Sz, M18-1.50 Ext Thrd Sz

The APPROVED VENDOR Key Locking Insert is a heavy-wall, mil. spec. insert with 4 keys, M12x1.25 internal thread size, M18-1.50 external thread size, plain finish, and 10 per pack. It meets Fed Std. H28/21 and MJ Form…

SKU 3G-OTH-531759

Brand
APPROVED VENDOR
Item
Key Locking Insert: Heavy Wall, 4 Keys, M12x1.25 Int Thrd Sz, M18-1.50 Ext Thrd Sz
Category
Mil. Spec. Key-Locking Inserts
Available to Order
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Technical Specifications

APPROVED VENDOR
Manufacturer Part Number
217-076569
Type
M12x1.25 Int Thrd Sz, M18-1.50 Ext Thrd Sz, Plain, 10 PK
Keys
4
Wall Type
Heavy Wall
Finish Type
Plain
Thread Type
Coarse
Drill Bit Size
16.70 mm
Industry Standards
Fed Std. H28/21, MJ Form
Compatible Tap Size
M18-1.50
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, M12x1.25 internal thread size, M18-1.50 external thread size, plain finish, and 10 per pack. It meets Fed Std. H28/21 and MJ Form standards, with 18-8 material, 2A external and 3B internal thread fits, compatible tap size M18-1.50, and drill bit size 16.70 mm.

Frequently Asked Questions

What is an APPROVED VENDOR key locking insert used for?

This heavy-wall key locking insert is used to repair or reinforce tapped threads in metal assemblies, particularly in aerospace and defense applications. It meets Fed Std. H28/21 and MJ Form standards, providing a durable 18-8 stainless steel thread with 4 locking keys to prevent rotation under vibration.

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

This insert has M12x1.25 internal thread size and M18-1.50 external thread size, with a heavy wall, plain finish, and 4 keys. It requires a 16.70 mm drill bit and M18-1.50 tap, with 2A external and 3B internal thread fits. Material is 18-8 stainless steel, meeting Fed Std. H28/21 and MJ Form standards.

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, regardless of location. Contact us for availability and lead time.

How to install an APPROVED VENDOR key locking insert?

Drill a 16.70 mm hole, tap it to M18-1.50 using a compatible tap, then thread the insert into the hole using a key locking insert installation tool. Ensure the 4 keys align with the tapped slots to lock the insert in place. Use a thread locking compound for critical applications.

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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