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APPROVED VENDOR Key Locking Insert: Heavy Wall, 4 Keys, 3/4"-10 Int Thrd Sz, 1 1/8"-12 Ext Thrd Sz - Mil. Spec. Key-Locking Inserts
APPROVED VENDORMil. Spec. Key-Locking Inserts

APPROVED VENDOR Key Locking Insert: Heavy Wall, 4 Keys, 3/4"-10 Int Thrd Sz, 1 1/8"-12 Ext Thrd Sz

The APPROVED VENDOR Key Locking Insert is a heavy-wall, mil-spec insert with 4 keys, 3/4"-10 internal thread size, and 1 1/8"-12 external thread size. It is plain finish, 18-8 material, meets MS51831-209, and comes…

SKU 3G-OTH-531729

Brand
APPROVED VENDOR
Item
Key Locking Insert: Heavy Wall, 4 Keys, 3/4"-10 Int Thrd Sz, 1 1/8"-12 Ext Thrd Sz
Category
Mil. Spec. Key-Locking Inserts
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Technical Specifications

APPROVED VENDOR
Manufacturer Part Number
217-076309
Type
Plain, 10 PK
Keys
4
Wall Type
Heavy Wall
Ext Thrd Sz
1 1/8"-12
Finish Type
Plain
Int Thrd Sz
3/4"-10
Thread Type
Coarse
Drill Bit Size
1-3/64 in
Industry Standards
MS51831-209
Compatible Tap Size
1-1/8"-12
External Thread Fit
2A
Internal Thread Fit
3B
Material Grade/Class
18-8
System of Measurement
Inch
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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, 3/4"-10 internal thread size, and 1 1/8"-12 external thread size. It is plain finish, 18-8 material, meets MS51831-209, and comes in a 10-pack. Compatible tap size is 1-1/8"-12; drill bit size is 1-3/64 in; external thread fit 2A; internal thread fit 3B.

Frequently Asked Questions

What is a key locking insert used for?

A key locking insert provides a durable, reusable thread in soft materials like aluminum or plastic. The heavy-wall design with 4 keys locks the insert in place, preventing rotation under vibration. It meets MS51831-209 for mil-spec applications, making it suitable for aerospace, defense, and industrial equipment requiring reliable threaded fasteners.

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

This heavy-wall insert has a 3/4"-10 internal thread and 1 1/8"-12 external thread, with 4 keys and a plain finish. It is made from 18-8 stainless steel, meets MS51831-209, and requires a 1-3/64 in drill bit and 1-1/8"-12 tap. External thread fit is 2A; internal thread fit is 3B. Sold in a 10-pack.

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 source this MS51831-209 compliant insert in a 10-pack, with lead time on request.

How to install a key locking insert?

Drill a hole to 1-3/64 in, tap it to 1-1/8"-12, then thread the insert in using a compatible installation tool. The 4 keys lock into the parent material to prevent loosening. Ensure the insert is flush or slightly below the surface. Use a thread locker for added security in high-vibration environments.

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.
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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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