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APPROVED VENDOR Key Locking Insert: Heavy Wall, 4 Keys, 5/8"-18 Int Thrd Sz, 7/8"-14 Ext Thrd Sz - Mil. Spec. Key-Locking Inserts
APPROVED VENDORMil. Spec. Key-Locking Inserts

APPROVED VENDOR Key Locking Insert: Heavy Wall, 4 Keys, 5/8"-18 Int Thrd Sz, 7/8"-14 Ext Thrd Sz

The APPROVED VENDOR Key Locking Insert is a heavy-wall, mil-spec insert with 4 keys, 5/8"-18 internal thread size, and 7/8"-14 external thread size. It is plain finish, 18-8 material, inch system, and meets…

SKU 3G-OTH-531764

Brand
APPROVED VENDOR
Item
Key Locking Insert: Heavy Wall, 4 Keys, 5/8"-18 Int Thrd Sz, 7/8"-14 Ext Thrd Sz
Category
Mil. Spec. Key-Locking Inserts
Available to Order
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Technical Specifications

APPROVED VENDOR
Manufacturer Part Number
217-077508
Type
Plain, 10 PK
Keys
4
Wall Type
Heavy Wall
Ext Thrd Sz
7/8"-14
Finish Type
Plain
Int Thrd Sz
5/8"-18
Thread Type
Coarse
Industry Standards
MS51831-109L
Compatible Tap Size
7/8"-14
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 heavy-wall, mil-spec insert with 4 keys, 5/8"-18 internal thread size, and 7/8"-14 external thread size. It is plain finish, 18-8 material, inch system, and meets MS51831-109L. Supplied as a 10-pack (MPN 217-077508).

Frequently Asked Questions

What is a key locking insert used for?

A key locking insert repairs or reinforces tapped holes in soft materials like aluminum. The external keys lock the insert in place, preventing rotation under vibration. This heavy-wall, mil-spec insert from APPROVED VENDOR is used in aerospace, defense, and industrial applications requiring reliable thread restoration.

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

This heavy-wall insert has a 5/8"-18 internal thread and 7/8"-14 external thread, with 4 keys. It is made of 18-8 stainless steel, plain finish, inch system, and meets MS51831-109L. External thread fit is 2A, internal fit is 3B. Supplied as a 10-pack (MPN 217-077508).

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 MS51831-109L compliant 10-pack.

How to install a key locking insert?

Installation requires drilling out the damaged thread to the specified tap size (7/8"-14), tapping the hole, then driving the insert using a key locking insert tool. The 4 keys lock into the parent material. Use thread locker for added security. Follow MS51831 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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