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APPROVED VENDOR Key Locking Insert: Thin Wall, 4 Keys, 1/4"-20 Int Thrd Sz, 3/8"-16 Ext Thrd Sz - Mil. Spec. Key-Locking Inserts
APPROVED VENDORMil. Spec. Key-Locking Inserts

APPROVED VENDOR Key Locking Insert: Thin Wall, 4 Keys, 1/4"-20 Int Thrd Sz, 3/8"-16 Ext Thrd Sz

The APPROVED VENDOR Key Locking Insert is a thin-wall, mil. spec. insert with 4 keys, a 1/4"-20 internal thread size, and a 3/8"-16 external thread size. It meets MS51831-101 standards, features 18-8 material, and…

SKU 3G-OTH-531753

Brand
APPROVED VENDOR
Item
Key Locking Insert: Thin Wall, 4 Keys, 1/4"-20 Int Thrd Sz, 3/8"-16 Ext Thrd Sz
Category
Mil. Spec. Key-Locking Inserts
Available to Order
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Technical Specifications

APPROVED VENDOR
Manufacturer Part Number
217-076322
Type
Plain, Plain, 10 PK
Keys
4
Wall Type
Thin Wall
Ext Thrd Sz
3/8"-16
Finish Type
Plain
Int Thrd Sz
1/4"-20
Thread Type
Coarse
Industry Standards
MS51831-101
Compatible Tap Size
3/8"-16
External Thread Fit
2A
Internal Thread Fit
3B
Material Grade/Class
18-8
System of Measurement
Inch
View Full Spec Sheet

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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, a 1/4"-20 internal thread size, and a 3/8"-16 external thread size. It meets MS51831-101 standards, features 18-8 material, and comes in a plain finish, 10-pack.

Frequently Asked Questions

What is a key locking insert used for?

A key locking insert repairs or reinforces tapped holes in softer materials, providing a durable 18-8 stainless steel thread. The 4 external keys lock the insert in place, preventing rotation under vibration. This thin-wall design meets MS51831-101 mil. spec. for aerospace, defense, and industrial applications.

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

This thin-wall insert has a 1/4"-20 internal thread and 3/8"-16 external thread, with 2A external and 3B internal thread fits. It is made from 18-8 stainless steel, plain finish, and includes 4 keys. It meets MS51831-101 standards and comes in a 10-pack (MPN 217-076322).

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 MS51831-101 compliant 10-pack (MPN 217-076322) for your maintenance or production needs.

How to install a key locking insert?

Installation requires drilling out the damaged thread, tapping to the specified compatible tap size (3/8"-16), then driving the insert using a key locking insert tool. The 4 keys embed into the parent material to prevent rotation. Use thread locker for added security. Follow MS51831-101 guidelines for torque and depth.

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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