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APPROVED VENDOR Key Locking Insert: Heavy Wall, 2 Keys, #6-32 Int Thrd Sz, 1/4"-20 Ext Thrd Sz - Mil. Spec. Key-Locking Inserts
APPROVED VENDORMil. Spec. Key-Locking Inserts

APPROVED VENDOR Key Locking Insert: Heavy Wall, 2 Keys, #6-32 Int Thrd Sz, 1/4"-20 Ext Thrd Sz

The APPROVED VENDOR Key Locking Insert is a heavy-wall, mil-spec insert (MIL-I-45914A / MS51831) with a #6-32 internal thread size and 1/4"-20 external thread size, supplied in a 10-pack. It features 2 keys, plain…

SKU 3G-OTH-531746

Brand
APPROVED VENDOR
Item
Key Locking Insert: Heavy Wall, 2 Keys, #6-32 Int Thrd Sz, 1/4"-20 Ext Thrd Sz
Category
Mil. Spec. Key-Locking Inserts
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Technical Specifications

APPROVED VENDOR
Manufacturer Part Number
217-077291
Type
#6-32 Int Thrd Sz, Plain, Plain, 10 PK
Keys
2
Wall Type
Heavy Wall
Ext Thrd Sz
1/4"-20
Finish Type
Plain
Thread Type
Coarse
Industry Standards
MIL-I-45914A (MS51831)
Compatible Tap Size
1/4"-20
External Thread Fit
2A
Internal Thread Fit
3B
Material Grade/Class
303
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 (MIL-I-45914A / MS51831) with a #6-32 internal thread size and 1/4"-20 external thread size, supplied in a 10-pack. It features 2 keys, plain finish, coarse thread, 303 stainless steel construction, and external/internal thread fits of 2A and 3B respectively.

Frequently Asked Questions

What is a key locking insert used for?

A key locking insert is used to repair or reinforce tapped holes in metal, providing a strong, reusable thread. The APPROVED VENDOR heavy-wall insert meets MIL-I-45914A (MS51831) for aerospace and defense applications, securing fasteners with its 2 keys to prevent rotation under vibration.

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

This heavy-wall insert has a #6-32 internal thread size and 1/4"-20 external thread size, with 2A external and 3B internal thread fits. It is made of 303 stainless steel, plain finish, coarse thread, and complies with MIL-I-45914A (MS51831). Supplied in a 10-pack.

Where to buy APPROVED VENDOR key locking inserts worldwide?

3G Electric supplies APPROVED VENDOR key locking inserts worldwide, handling full logistics and customs clearance. As a global industrial solutions provider, we source and deliver genuine mil-spec inserts like the 217-077291 to any location, ensuring compliance with your procurement requirements.

How to install a key locking insert?

Installation requires drilling to the specified tap size (1/4"-20), tapping the hole, then driving the insert using a compatible tool until the keys engage. The 2 keys lock the insert in place, preventing rotation. Always follow MIL-I-45914A guidelines for torque and depth to ensure a secure fit.

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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