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E-Z LOK Self Locking Thread Insert: Heavy Wall, 1/4"-28 Int Thrd Sz, 7/16"-14 Ext Thrd Sz - Heavy Wall Self-Locking Inserts
E-Z LOKHeavy Wall Self-Locking Inserts

E-Z LOK Self Locking Thread Insert: Heavy Wall, 1/4"-28 Int Thrd Sz, 7/16"-14 Ext Thrd Sz

The E-Z LOK Self Locking Thread Insert is a heavy-wall, inch-system insert with a 1/4"-28 UNF internal thread and a 7/16"-14 UNC external thread, supplied as a 5-pack (MPN 303-428-PK5). It features a 2B internal…

SKU 3G-OTH-534110

Brand
E-Z LOK
Item
Self Locking Thread Insert: Heavy Wall, 1/4"-28 Int Thrd Sz, 7/16"-14 Ext Thrd Sz
Category
Heavy Wall Self-Locking Inserts
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Technical Specifications

E-Z LOK
Manufacturer Part Number
303-428-PK5
Type
5 PK
Wall Type
Heavy Wall
Ext Thrd Sz
7/16"-14
Int Thrd Sz
1/4"-28
Thread Type
UNF Internal/UNC External
Compatible Tap Size
7/16"-14
External Thread Fit
2A
Internal Thread Fit
2B
System of Measurement
Inch
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E-Z LOK Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The E-Z LOK Self Locking Thread Insert is a heavy-wall, inch-system insert with a 1/4"-28 UNF internal thread and a 7/16"-14 UNC external thread, supplied as a 5-pack (MPN 303-428-PK5). It features a 2B internal thread fit and a 2A external thread fit, compatible with a 7/16"-14 tap. 3G Electric sources this genuine OEM component across 14 industrial departments, with specialist expertise in fastening and assembly solutions.

Frequently Asked Questions

What is E-Z LOK Self Locking Thread Insert used for?

E-Z LOK Self Locking Thread Inserts repair or reinforce tapped holes in metal, plastic, or wood. The heavy-wall design provides strong, wear-resistant threads for demanding industrial applications. 3G Electric supplies this genuine OEM component across 14 industrial departments, with specialist expertise in fastening and assembly solutions.

What are the specifications of E-Z LOK 303-428-PK5?

This heavy-wall insert has a 1/4"-28 UNF internal thread and a 7/16"-14 UNC external thread, with 2B internal and 2A external thread fits. It is compatible with a 7/16"-14 tap, uses inch measurement, and comes as a 5-pack (MPN 303-428-PK5).

Where to buy E-Z LOK thread inserts in worldwide?

3G Electric supplies E-Z LOK thread inserts worldwide, handling full logistics and customs clearance. As a global industrial solutions provider, we source genuine OEM components across 14 departments. Contact us for pricing and delivery to your location.

How to install E-Z LOK self locking thread inserts?

Installation requires tapping a hole to the specified external thread size (7/16"-14), then driving the insert into the tapped hole using a standard installation tool. The self-locking feature engages upon insertion. Always follow the manufacturer's instructions for torque and depth.

E-Z LOK Products

3G Electric supplies E-Z LOK 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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E-Z LOK Self Locking Thread Insert: Heavy Wall, 1"-8 Int Thrd Sz, 1 3/8"-12 Ext Thrd Sz, Steel, 5 PK (MPN 329-16-PK5). Key specifications — Compatible Tap Size: 1-3/8"-12; Internal Thread Fit: 2B; System of Measurement: Inch; Thread Type: Coarse; Wall Type: Heavy Wall; External Thread Fit: 2A.
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E-Z LOK Self Locking Thread Insert: Heavy Wall, 1"-8 Int Thrd Sz, 1 3/8"-12 Ext Thrd Sz, Steel, 5 PK (MPN 329-16-PK5). Key specifications — Compatible Tap Size: 1-3/8"-12; Internal Thread Fit: 2B; System of Measurement: Inch; Thread Type: Coarse; Wall Type: Heavy Wall; External Thread Fit: 2A.
E-Z LOK Self Locking Thread Insert: Heavy Wall, 9/16"-12 Int Thrd Sz, 3/4"-10 Ext Thrd Sz, 5 PK (MPN 329-9-PK5). Key specifications — Compatible Tap Size: 3/4"-10; Internal Thread Fit: 2B; System of Measurement: Inch; Thread Type: Coarse; Wall Type: Heavy Wall; External Thread Fit: 2A.
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E-Z LOK Self Locking Thread Insert: Heavy Wall, 9/16"-12 Int Thrd Sz, 3/4"-10 Ext Thrd Sz, 5 PK (MPN 329-9-PK5). Key specifications — Compatible Tap Size: 3/4"-10; Internal Thread Fit: 2B; System of Measurement: Inch; Thread Type: Coarse; Wall Type: Heavy Wall; External Thread Fit: 2A.
E-Z LOK Self Locking Thread Insert: Heavy Wall, M20-2.50 Int Thrd Sz, M36-4.00 Ext Thrd Sz, 5 PK (MPN 450-20-PK5). Key specifications — Compatible Tap Size: M36-4.00; Internal Thread Fit: 6H; System of Measurement: Metric; Thread Type: Metric; Wall Type: Heavy Wall; Drill Bit Size: 33 mm; External Thread Fit: 6G.
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E-Z LOK Self Locking Thread Insert: Heavy Wall, M20-2.50 Int Thrd Sz, M36-4.00 Ext Thrd Sz, 5 PK (MPN 450-20-PK5). Key specifications — Compatible Tap Size: M36-4.00; Internal Thread Fit: 6H; System of Measurement: Metric; Thread Type: Metric; Wall Type: Heavy Wall; Drill Bit Size: 33 mm; External Thread Fit: 6G.
E-Z LOK Self Locking Thread Insert: Heavy Wall, 3/8"-16 Int Thrd Sz, M16-2.00 Ext Thrd Sz, 5 PK (MPN 550-6-PK5). Key specifications — Compatible Tap Size: M16-2.00; Internal Thread Fit: 2B; System of Measurement: Inch/Metric; Thread Type: UNC Internal/Metric External; Wall Type: Heavy Wall; Drill Bit Size: 14 mm; External Thread Fit: 2A.
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E-Z LOK Self Locking Thread Insert: Heavy Wall, 3/8"-16 Int Thrd Sz, M16-2.00 Ext Thrd Sz, 5 PK (MPN 550-6-PK5). Key specifications — Compatible Tap Size: M16-2.00; Internal Thread Fit: 2B; System of Measurement: Inch/Metric; Thread Type: UNC Internal/Metric External; Wall Type: Heavy Wall; Drill Bit Size: 14 mm; External Thread Fit: 2A.
E-Z LOK Self Locking Thread Insert: Heavy Wall, M4-0.70 Int Thrd Sz, M8-1.25 Ext Thrd Sz, 10 PK (MPN 450-4-PK10). Key specifications — Compatible Tap Size: M8-1.25; Internal Thread Fit: 6H; System of Measurement: Metric; Thread Type: Metric; Wall Type: Heavy Wall; External Thread Fit: 6G.
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E-Z LOK Self Locking Thread Insert: Heavy Wall, M4-0.70 Int Thrd Sz, M8-1.25 Ext Thrd Sz, 10 PK (MPN 450-4-PK10). Key specifications — Compatible Tap Size: M8-1.25; Internal Thread Fit: 6H; System of Measurement: Metric; Thread Type: Metric; Wall Type: Heavy Wall; External Thread Fit: 6G.
E-Z LOK Self Locking Thread Insert: Heavy Wall, M14-2.00 Int Thrd Sz, 7/8"-9 Ext Thrd Sz, 5 PK (MPN 650-14-PK5). Key specifications — Compatible Tap Size: 7/8"-9; Internal Thread Fit: 2B; System of Measurement: Inch/Metric; Thread Type: Metric Internal/UNC External; Wall Type: Heavy Wall; External Thread Fit: 2A.
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E-Z LOK Self Locking Thread Insert: Heavy Wall, M14-2.00 Int Thrd Sz, 7/8"-9 Ext Thrd Sz, 5 PK (MPN 650-14-PK5). Key specifications — Compatible Tap Size: 7/8"-9; Internal Thread Fit: 2B; System of Measurement: Inch/Metric; Thread Type: Metric Internal/UNC External; Wall Type: Heavy Wall; External Thread Fit: 2A.
E-Z LOK Self Locking Thread Insert: Heavy Wall, M3-0.50 Int Thrd Sz, M6-1.00 Ext Thrd Sz, 10 PK (MPN 450-3-PK10). Key specifications — Compatible Tap Size: M6-1.00; Internal Thread Fit: 6H; System of Measurement: Metric; Thread Type: Metric; Wall Type: Heavy Wall; External Thread Fit: 6G.
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E-Z LOK Self Locking Thread Insert: Heavy Wall, M3-0.50 Int Thrd Sz, M6-1.00 Ext Thrd Sz, 10 PK (MPN 450-3-PK10). Key specifications — Compatible Tap Size: M6-1.00; Internal Thread Fit: 6H; System of Measurement: Metric; Thread Type: Metric; Wall Type: Heavy Wall; External Thread Fit: 6G.
E-Z LOK Self Locking Thread Insert: Heavy Wall, 5/16"-18 Int Thrd Sz, 1/2"-13 Ext Thrd Sz, 10 PK (MPN 329-5-PK10). Key specifications — Compatible Tap Size: 1/2"-13; Internal Thread Fit: 2B; System of Measurement: Inch; Thread Type: Coarse; Wall Type: Heavy Wall; External Thread Fit: 2A.
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E-Z LOK Self Locking Thread Insert: Heavy Wall, 5/16"-18 Int Thrd Sz, 1/2"-13 Ext Thrd Sz, 10 PK (MPN 329-5-PK10). Key specifications — Compatible Tap Size: 1/2"-13; Internal Thread Fit: 2B; System of Measurement: Inch; Thread Type: Coarse; Wall Type: Heavy Wall; External Thread Fit: 2A.