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HELI-COIL Helical Insert: Tangless Tang Style, Free-Running, 1/4"-28 Thread Size - Free-Running Tangless Helical Inserts
HELI-COILFree-Running Tangless Helical Inserts

HELI-COIL Helical Insert: Tangless Tang Style, Free-Running, 1/4"-28 Thread Size

The HELI-COIL Helical Insert is a free-running, tangless tang-style insert with a 1/4"-28 fine thread, right-hand direction, and plain finish. Supplied in a 100-pack, it is made from 18-8 material with a tensile…

SKU 3G-OTH-527337

Brand
HELI-COIL
Item
Helical Insert: Tangless Tang Style, Free-Running, 1/4"-28 Thread Size
Category
Free-Running Tangless Helical Inserts
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Technical Specifications

HELI-COIL
Manufacturer Part Number
AT1191-4C375
Type
Free-Running, Plain, 100 PK
Tensile Strength
200,000 to 250,000 psi
Finish Type
Plain
Thread Size
1/4"-28
Thread Type
Fine
STI Tap Size
#10-32
Thread Direction
Right Hand
Compatible Material
Metal
Material Grade/Class
18-8
System of Measurement
Inch
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HELI-COIL Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The HELI-COIL Helical Insert is a free-running, tangless tang-style insert with a 1/4"-28 fine thread, right-hand direction, and plain finish. Supplied in a 100-pack, it is made from 18-8 material with a tensile strength of 200,000 to 250,000 psi, compatible with metal, and requires an STI tap size of #10-32.

Frequently Asked Questions

What is a HELI-COIL tangless helical insert used for?

A HELI-COIL tangless helical insert repairs or reinforces threads in metal components. It provides a durable, free-running internal thread for fasteners, commonly used in automotive, aerospace, and industrial maintenance applications where stripped or worn threads need restoration.

What are the specifications of the HELI-COIL AT1191-4C375 insert?

This HELI-COIL insert has a 1/4\"-28 fine thread, right-hand direction, and plain finish. It is made from 18-8 material with a tensile strength of 200,000 to 250,000 psi. The STI tap size is #10-32, and it comes in a 100-pack for metal applications.

Where to buy HELI-COIL helical inserts worldwide?

3G Electric supplies HELI-COIL helical inserts worldwide. As a global industrial solutions provider, we handle full logistics and customs clearance to deliver this 100-pack of tangless inserts to your facility, ensuring you get the right thread repair solution for your application.

How to install a HELI-COIL tangless insert?

To install a HELI-COIL tangless insert, drill the hole to the specified size, tap it using the correct STI tap (size #10-32 for this insert), then use a tangless installation tool to wind the insert into the tapped hole. No tang removal is needed, simplifying the process.

Used in

Common applications for HELI-COIL
Aerospace engine repair — HELI-COIL STI taps for M12x1.75 metric threads in aluminum alloy components
Automotive transmission rebuild — HELI-COIL STI taps for 7/16-14 UNC threads in cast iron housings
Industrial pump maintenance — HELI-COIL STI taps for #10-32 UNF threads in stainless steel pump bodies
Hydraulic cylinder repair — HELI-COIL STI taps for M6x1 metric threads in steel cylinder heads
General manufacturing — HELI-COIL STI taps for 9/16-18 UNF threads in machinery base plates

HELI-COIL Products

3G Electric supplies HELI-COIL free-running tangless helical inserts. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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HELI-COIL Helical Insert: Tangless Tang Style, Free-Running, #6-32 Thread Size, Plain, Plain, 100 PK (MPN AT1185-06C276). Key specifications — Material Grade/Class: 18-8; Thread Direction: Right Hand; STI Tap Size: #6-32; Compatible Material: Metal; System of Measurement: Inch; Brand: HELI-COIL; Tensile Strength: 200,000 to 250,000 psi; Thread Type: Coarse.
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HELI-COIL Helical Insert: Tangless Tang Style, Free-Running, #6-32 Thread Size, Plain, Plain, 100 PK (MPN AT1185-06C276). Key specifications — Material Grade/Class: 18-8; Thread Direction: Right Hand; STI Tap Size: #6-32; Compatible Material: Metal; System of Measurement: Inch; Brand: HELI-COIL; Tensile Strength: 200,000 to 250,000 psi; Thread Type: Coarse.
HELI-COIL Helical Insert: Tangless Tang Style, Free-Running, #10-32 Thread Size, Plain, 100 PK (MPN AT1191-3C285). Key specifications — Material Grade/Class: 18-8; Thread Direction: Right Hand; STI Tap Size: #10-32; Compatible Material: Metal; System of Measurement: Inch; Brand: HELI-COIL; Tensile Strength: 200,000 to 250,000 psi; Thread Type: Fine.
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HELI-COIL Helical Insert: Tangless Tang Style, Free-Running, #10-32 Thread Size, Plain, 100 PK (MPN AT1191-3C285). Key specifications — Material Grade/Class: 18-8; Thread Direction: Right Hand; STI Tap Size: #10-32; Compatible Material: Metal; System of Measurement: Inch; Brand: HELI-COIL; Tensile Strength: 200,000 to 250,000 psi; Thread Type: Fine.
HELI-COIL Helical Insert: Tangless Tang Style, Free-Running, #6-32 Thread Size, Plain, Plain, 100 PK (MPN AT1185-06C207). Key specifications — Material Grade/Class: 18-8; Thread Direction: Right Hand; STI Tap Size: #6-32; Compatible Material: Metal; System of Measurement: Inch; Brand: HELI-COIL; Tensile Strength: 200,000 to 250,000 psi; Thread Type: Coarse.
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HELI-COIL Helical Insert: Tangless Tang Style, Free-Running, #10-32 Thread Size, Plain, 100 PK (MPN AT1191-3C380). Key specifications — Material Grade/Class: 18-8; Thread Direction: Right Hand; STI Tap Size: #10-32; Compatible Material: Metal; System of Measurement: Inch; Brand: HELI-COIL; Tensile Strength: 200,000 to 250,000 psi; Thread Type: Fine.
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HELI-COIL Helical Insert: Tangless Tang Style, Free-Running, #2-56 Thread Size, Plain, Plain, 100 PK (MPN AT1185-02C129). Key specifications — Material Grade/Class: 18-8; Thread Direction: Right Hand; STI Tap Size: #2-56; Compatible Material: Metal; System of Measurement: Inch; Brand: HELI-COIL; Tensile Strength: 200,000 to 250,000 psi; Thread Type: Coarse.
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