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APPROVED VENDOR Self Locking Thread Insert: Heavy Wall, 1/4"-20 Int Thrd Sz, 1 in Overall Lg - Heavy Wall Self-Locking Inserts
APPROVED VENDORHeavy Wall Self-Locking Inserts

APPROVED VENDOR Self Locking Thread Insert: Heavy Wall, 1/4"-20 Int Thrd Sz, 1 in Overall Lg

The APPROVED VENDOR Self Locking Thread Insert is a heavy-wall, inch-system insert with a 1/4"-20 internal coarse thread and 1 in overall length, supplied in a 5-pack (MPN 329-401-PK5). It requires a 7/16"-14 tap and…

SKU 3G-OTH-534108

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APPROVED VENDOR
Item
Self Locking Thread Insert: Heavy Wall, 1/4"-20 Int Thrd Sz, 1 in Overall Lg
Category
Heavy Wall Self-Locking Inserts
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Technical Specifications

APPROVED VENDOR
Manufacturer Part Number
329-401-PK5
Type
5 PK
Overall Lg
1 in
Wall Type
Heavy Wall
Int Thrd Sz
1/4"-20
Thread Type
Coarse
Compatible Tap Size
7/16"-14
External Thread Fit
2A
Internal Thread Fit
2B
System of Measurement
Inch
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APPROVED VENDOR Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The APPROVED VENDOR Self Locking Thread Insert is a heavy-wall, inch-system insert with a 1/4"-20 internal coarse thread and 1 in overall length, supplied in a 5-pack (MPN 329-401-PK5). It requires a 7/16"-14 tap and features external thread fit 2A and internal thread fit 2B.

Frequently Asked Questions

What is an APPROVED VENDOR heavy wall self-locking thread insert used for?

This heavy wall self-locking thread insert repairs or reinforces stripped internal threads in metal assemblies. It is used across industrial maintenance, machining, and repair applications where a 1/4"-20 coarse thread is needed, providing a durable, locking thread that resists vibration loosening.

What are the specifications of the APPROVED VENDOR 329-401-PK5 thread insert?

The APPROVED VENDOR 329-401-PK5 is a 5-pack of heavy wall self-locking inserts with 1/4"-20 internal coarse thread, 1 in overall length, and 2B internal thread fit. It requires a 7/16"-14 tap and has external thread fit 2A. System of measurement is inch.

Where to buy APPROVED VENDOR thread inserts worldwide?

3G Electric supplies APPROVED VENDOR self-locking thread inserts worldwide. As a global industrial solutions provider, we handle full logistics, customs clearance, and delivery to your facility. Contact us for pricing and lead time on the 329-401-PK5 5-pack or other thread repair inserts.

How to install a heavy wall self-locking thread insert?

To install, drill out the damaged thread to the recommended size, then tap the hole using a 7/16"-14 tap for this insert. Use a proper installation tool to drive the insert until it is slightly below the surface. The self-locking feature engages upon insertion, securing the insert without additional adhesives.

Used in

Common applications for APPROVED VENDOR
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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 heavy wall self-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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APPROVED VENDOR Self Locking Thread Insert: Std Wall, #4-40 Int Thrd Sz, #10-32 Ext Thrd Sz, Plain (MPN 316-004). Key specifications — Compatible Tap Size: #10-32; Internal Thread Fit: 2B; System of Measurement: Inch; Thread Type: Fine; Wall Type: Standard Wall; Drill Bit Size: 5/32; External Thread Fit: 2A.
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APPROVED VENDOR Self Locking Thread Insert: Std Wall, M5-0.80 Int Thrd Sz, M8-1.25 Ext Thrd Sz (MPN 416-5). Key specifications — Compatible Tap Size: M8-1.25; Internal Thread Fit: 6H; System of Measurement: Metric; Thread Type: Coarse; Wall Type: Standard Wall; Drill Bit Size: 6.9mm; External Thread Fit: 6G.
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APPROVED VENDOR Self Locking Thread Insert: Std Wall, M5-0.80 Int Thrd Sz, M8-1.25 Ext Thrd Sz (MPN 416-5). Key specifications — Compatible Tap Size: M8-1.25; Internal Thread Fit: 6H; System of Measurement: Metric; Thread Type: Coarse; Wall Type: Standard Wall; Drill Bit Size: 6.9mm; External Thread Fit: 6G.
APPROVED VENDOR Self Locking Thread Insert: Std Wall, 1/4"-20 Int Thrd Sz, 7/16"-14 Ext Thrd Sz (MPN 316-4). Key specifications — Compatible Tap Size: 7/16"-14; Internal Thread Fit: 2B; System of Measurement: Inch; Thread Type: Coarse; Wall Type: Standard Wall; External Thread Fit: 2A.
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APPROVED VENDOR Self Locking Thread Insert: Std Wall, 1/4"-20 Int Thrd Sz, 7/16"-14 Ext Thrd Sz (MPN 316-4). Key specifications — Compatible Tap Size: 7/16"-14; Internal Thread Fit: 2B; System of Measurement: Inch; Thread Type: Coarse; Wall Type: Standard Wall; External Thread Fit: 2A.
APPROVED VENDOR Self Locking Thread Insert: Std Wall, #6-32 Int Thrd Sz, 1/4"-20 Ext Thrd Sz, Plain (MPN 316-006). Key specifications — Compatible Tap Size: 1/4"-20; Internal Thread Fit: 2B; System of Measurement: Inch; Thread Type: Fine; Wall Type: Standard Wall; Drill Bit Size: 7; External Thread Fit: 2A.
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APPROVED VENDOR Self Locking Thread Insert: Std Wall, M10-1.50 Int Thrd Sz, M16-2.00 Ext Thrd Sz (MPN 416-10). Key specifications — Compatible Tap Size: M16-2.00; Internal Thread Fit: 6H; System of Measurement: Metric; Thread Type: Coarse; Wall Type: Standard Wall; Drill Bit Size: 14mm; External Thread Fit: 6G.
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APPROVED VENDOR Self Locking Thread Insert: Std Wall, 3/8"-16 Int Thrd Sz, 9/16"-12 Ext Thrd Sz (MPN 316-6). Key specifications — Compatible Tap Size: 9/16"-12; Internal Thread Fit: 2B; System of Measurement: Inch; Thread Type: Fine; Wall Type: Standard Wall; Drill Bit Size: 31/64; External Thread Fit: 2A.
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APPROVED VENDOR Self Locking Thread Insert: Heavy Wall, 5/16"-18 Int Thrd Sz, 1 in Overall Lg, 5 PK (MPN 329-501-PK5). Key specifications — Compatible Tap Size: 1/2"-13; Internal Thread Fit: 2B; System of Measurement: Inch; Thread Type: Coarse; Wall Type: Heavy Wall; Drill Bit Size: 27/64; External Thread Fit: 2A.
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