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APPROVED VENDOR Key Locking Insert: Thin Wall, 4 Keys, 1/4"-28 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"-28 Int Thrd Sz, 3/8"-16 Ext Thrd Sz

The APPROVED VENDOR Key Locking Insert is a thin-wall, inch-system Mil. Spec. insert with 4 keys, 1/4"-28 internal thread size, and 3/8"-16 external thread size. It is made of 18-8 material, features a plain finish…

SKU 3G-OTH-531723

Brand
APPROVED VENDOR
Item
Key Locking Insert: Thin Wall, 4 Keys, 1/4"-28 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
217-076522
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"-28
Thread Type
Coarse
Industry Standards
MS51831-107
Compatible Tap Size
3/8"-16
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 thin-wall, inch-system Mil. Spec. insert with 4 keys, 1/4"-28 internal thread size, and 3/8"-16 external thread size. It is made of 18-8 material, features a plain finish, and meets MS51831-107 standards. Supplied as a 10-pack with 2A external and 3B internal thread fits, it is compatible with a 3/8"-16 tap.

Frequently Asked Questions

What is an APPROVED VENDOR Key Locking Insert used for?

This thin-wall key locking insert repairs or strengthens threads in metal assemblies, typically in aerospace, defense, or industrial equipment. Its four keys lock it into place, preventing rotation under vibration. The 1/4"-28 internal thread accepts a fastener, while the 3/8"-16 external thread installs into a tapped hole.

What are the specifications of the APPROVED VENDOR 217-076522 Key Locking Insert?

This 10-pack insert has a 1/4"-28 internal thread size and 3/8"-16 external thread size, with 2A external and 3B internal thread fits. It is made of 18-8 stainless steel, has a plain finish, and meets MS51831-107 standards. Compatible tap size is 3/8"-16.

Where to buy APPROVED VENDOR Key Locking Inserts worldwide?

3G Electric supplies APPROVED VENDOR key locking inserts to customers worldwide. We handle full logistics, customs clearance, and delivery to your facility. Contact us for pricing and lead time on this MS51831-107 compliant insert.

How to install a thin-wall key locking insert?

Drill and tap the hole to the specified compatible tap size (3/8"-16). Use an installation tool to thread the insert into the tapped hole until the keys are flush or slightly below the surface. Then set the keys using a key-setting tool to lock the insert in place.

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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