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APPROVED VENDOR Key Locking Insert: Heavy Wall, 4 Keys, 3/4"-16 Int Thrd Sz, 2 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"-16 Int Thrd Sz, 2 1/8"-12 Ext Thrd Sz

The APPROVED VENDOR Key Locking Insert is a heavy-wall, mil. spec. key-locking insert with 4 keys, a 3/4"-16 internal thread size, and a 2 1/8"-12 external thread size. It is plain finished, comes in a 10-pack, and…

SKU 3G-OTH-531670

Brand
APPROVED VENDOR
Item
Key Locking Insert: Heavy Wall, 4 Keys, 3/4"-16 Int Thrd Sz, 2 1/8"-12 Ext Thrd Sz
Category
Mil. Spec. Key-Locking Inserts
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Technical Specifications

APPROVED VENDOR
Manufacturer Part Number
217-077509
Type
Plain, 10 PK
Keys
4
Wall Type
Heavy Wall
Ext Thrd Sz
2 1/8"-12
Finish Type
Plain
Int Thrd Sz
3/4"-16
Thread Type
Coarse
Industry Standards
MS51831-110L
Compatible Tap Size
1-1/8"-12
External Thread Fit
2A
Internal Thread Fit
3B
External Thread Size
2-1/8"-12
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. key-locking insert with 4 keys, a 3/4"-16 internal thread size, and a 2 1/8"-12 external thread size. It is plain finished, comes in a 10-pack, and is made from 18-8 material. This insert meets industry standard MS51831-110L and has a compatible tap size of 1-1/8"-12, with external thread fit 2A and internal thread fit 3B.

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 external keys lock the insert into the parent material, preventing rotation under load. This heavy-wall, 18-8 stainless steel insert meets MS51831-110L and is used in aerospace, defense, and industrial assemblies requiring high-strength thread repair.

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

This heavy-wall insert has a 3/4"-16 internal thread and a 2 1/8"-12 external thread, with 4 keys and a plain finish. It is made from 18-8 stainless steel, meets MS51831-110L, and has a compatible tap size of 1-1/8"-12. External thread fit is 2A; internal thread fit is 3B. Supplied 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 for pricing and lead time on this MS51831-110L heavy-wall insert in a 10-pack.

How to install a key locking insert?

Drill and tap the hole to the compatible tap size (1-1/8"-12 for this insert). Use a key locking insert installation tool to drive the insert into the tapped hole until the keys engage. Ensure the insert is flush or slightly below the surface. No thread locking compound is needed due to the mechanical key lock.

Used in

Common applications for APPROVED VENDOR
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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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