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APPROVED VENDOR Key Locking Insert: Heavy Wall, 4 Keys, 1/4"-28 Int Thrd Sz, 7/16"-14 Ext Thrd Sz - Mil. Spec. Key-Locking Inserts
APPROVED VENDORMil. Spec. Key-Locking Inserts

APPROVED VENDOR Key Locking Insert: Heavy Wall, 4 Keys, 1/4"-28 Int Thrd Sz, 7/16"-14 Ext Thrd Sz

The APPROVED VENDOR Key Locking Insert is a heavy-wall, mil-spec insert with 4 keys, a 1/4"-28 internal thread size, and a 7/16"-14 external thread size. It is plain finish, 18-8 material, inch system, and meets…

SKU 3G-OTH-531636

Brand
APPROVED VENDOR
Item
Key Locking Insert: Heavy Wall, 4 Keys, 1/4"-28 Int Thrd Sz, 7/16"-14 Ext Thrd Sz
Category
Mil. Spec. Key-Locking Inserts
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Technical Specifications

APPROVED VENDOR
Manufacturer Part Number
217-077502
Type
Plain, 10 PK
Keys
4
Wall Type
Heavy Wall
Ext Thrd Sz
7/16"-14
Finish Type
Plain
Int Thrd Sz
1/4"-28
Thread Type
Coarse
Industry Standards
MS51831-103L
Compatible Tap Size
7/16"-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, a 1/4"-28 internal thread size, and a 7/16"-14 external thread size. It is plain finish, 18-8 material, inch system, and meets MS51831-103L. Supplied in a 10-pack, this insert is compatible with a 7/16"-14 tap and has external thread fit 2A and internal thread fit 3B.

Supplied to the Philippines — compatible with 60 Hz installations. DHL Express delivery to Manila, Quezon City, Cebu, customs and duties handled door-to-door.

Frequently Asked Questions

What is a key locking insert used for?

A key locking insert is used to repair or reinforce tapped threads in metal assemblies, especially in aerospace and defense applications. The APPROVED VENDOR heavy-wall insert with 4 keys provides a permanent, vibration-resistant thread in soft materials like aluminum, meeting mil-spec MS51831-103L for critical fastening.

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

This heavy-wall insert has a 1/4"-28 internal thread and 7/16"-14 external thread, with 4 keys and a plain finish. It is made from 18-8 stainless steel, inch system, with external thread fit 2A and internal thread fit 3B. It meets MS51831-103L and comes in a 10-pack.

Where to buy APPROVED VENDOR key locking inserts worldwide?

3G Electric supplies the APPROVED VENDOR key locking insert (MPN 217-077502) to customers worldwide. We handle full logistics, customs clearance, and delivery to your facility. Contact us for pricing and lead time on this mil-spec insert.

How to install a key locking insert?

Installation requires tapping the hole to the compatible tap size (7/16"-14), then driving the insert using a key locking insert tool until it is flush or slightly below the surface. The 4 keys are then set into the parent material to prevent rotation. Follow standard mil-spec installation practices for best results.

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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