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APPROVED VENDOR Key Locking Insert: Thin Wall, 4 Keys, 7/16"-14 Int Thrd Sz, 9/16"-12 Ext Thrd Sz - Mil. Spec. Key-Locking Inserts
APPROVED VENDORMil. Spec. Key-Locking Inserts

APPROVED VENDOR Key Locking Insert: Thin Wall, 4 Keys, 7/16"-14 Int Thrd Sz, 9/16"-12 Ext Thrd Sz

The APPROVED VENDOR Key Locking Insert is a thin-wall, 4-key, plain-finish Mil. Spec. insert (MS51831-104) with a 7/16"-14 internal thread and 9/16"-12 external thread, supplied in a 10-pack. Made from 18-8 material…

SKU 3G-OTH-531748

Brand
APPROVED VENDOR
Item
Key Locking Insert: Thin Wall, 4 Keys, 7/16"-14 Int Thrd Sz, 9/16"-12 Ext Thrd Sz
Category
Mil. Spec. Key-Locking Inserts
Available to Order
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Technical Specifications

APPROVED VENDOR
Manufacturer Part Number
217-076325
Type
Plain, 10 PK
Keys
4
Wall Type
Thin Wall
Ext Thrd Sz
9/16"-12
Finish Type
Plain
Int Thrd Sz
7/16"-14
Thread Type
Coarse
Industry Standards
MS51831-104
Compatible Tap Size
9/16"-12
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, 4-key, plain-finish Mil. Spec. insert (MS51831-104) with a 7/16"-14 internal thread and 9/16"-12 external thread, supplied in a 10-pack. Made from 18-8 material with 2A external and 3B internal thread fits, it is compatible with a 9/16"-12 tap and uses inch measurements.

Frequently Asked Questions

What is an APPROVED VENDOR Key Locking Insert used for?

This thin-wall, 4-key insert repairs or reinforces stripped internal threads in metal assemblies. It meets Mil. Spec. MS51831-104 for aerospace, defense, and industrial applications requiring a secure, vibration-resistant thread. The 18-8 stainless steel construction provides corrosion resistance in demanding environments.

What are the specifications of the APPROVED VENDOR 217-076325 Key Locking Insert?

This 10-pack insert has a 7/16"-14 internal thread and 9/16"-12 external thread with coarse thread type. It features 4 keys, thin wall design, plain finish, 2A external and 3B internal thread fits, and is made from 18-8 material. Compatible tap size is 9/16"-12, meeting MS51831-104 standards.

Where to buy APPROVED VENDOR Key Locking Inserts worldwide?

3G Electric supplies APPROVED VENDOR Key Locking Inserts to global customers. As a sourcing partner, we handle logistics, customs clearance, and delivery worldwide. Contact us for availability and lead time on this MS51831-104 insert in a 10-pack.

How to install an APPROVED VENDOR Key Locking Insert?

Install using a compatible 9/16"-12 tap to prepare the hole, then drive the insert with a key-locking installation tool until the keys engage. Ensure the external thread fit (2A) aligns with the parent material. Follow standard Mil. Spec. MS51831-104 procedures for proper seating and torque.

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.
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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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