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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, inch-system Mil. Spec. insert with 4 keys, 1/4"-20 internal thread size, and 3/8"-16 external thread size. It is made from 18-8 material, features plain finish…

SKU 3G-OTH-531631

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
217-077322
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
MS51830-110
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"-20 internal thread size, and 3/8"-16 external thread size. It is made from 18-8 material, features plain finish, and meets MS51830-110 standards with external thread fit 2A and internal thread fit 3B. Supplied as a 10-pack (MPN 217-077322), this insert 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 is used to repair or reinforce threaded holes in metal assemblies, particularly in aerospace and defense applications. It meets Mil. Spec. MS51830-110, providing a secure 1/4"-20 internal thread with 4 locking keys to prevent rotation under vibration.

What are the specifications of the APPROVED VENDOR 217-077322 key locking insert?

This 10-pack insert has a 1/4"-20 internal thread size and 3/8"-16 external thread size, with 2A external and 3B internal thread fits. It is made from 18-8 stainless steel with a plain finish, compatible with a 3/8"-16 tap, and meets MS51830-110 standards.

Where to buy APPROVED VENDOR key locking inserts worldwide?

3G Electric supplies the APPROVED VENDOR 217-077322 key locking insert to customers worldwide. We handle full logistics and customs clearance, sourcing genuine Mil. Spec. inserts from our global supply network. Contact us for pricing and delivery to your location.

How to install a thin-wall key locking insert?

Installation requires tapping the hole to the specified 3/8"-16 thread size, then driving the insert using a compatible installation tool until it is flush or slightly below the surface. The 4 keys are then set into the parent material to lock the insert in place, preventing rotation.

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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