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

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

The HELI-COIL Helical Insert is a free-running, tanged tang style insert with a 1/4"-28 thread size, right-hand orientation, and fine thread pitch. Made from 18-8 metal, it offers a tensile strength of 200,000 to…

SKU 3G-OTH-598921

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

HELI-COIL
Manufacturer Part Number
1191-4CN375S
Type
Free-Running, Plain, 1,000 PK
Thread Size
1/4"-28
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HELI-COIL Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The HELI-COIL Helical Insert is a free-running, tanged tang style insert with a 1/4"-28 thread size, right-hand orientation, and fine thread pitch. Made from 18-8 metal, it offers a tensile strength of 200,000 to 250,000 psi and comes in a plain finish, packaged as 1,000 pieces (MPN 1191-4CN375S).

Frequently Asked Questions

What is a HELI-COIL helical insert used for?

A HELI-COIL helical insert repairs or reinforces tapped threads in metal, preventing stripping in soft materials like aluminum. It is ideal for automotive, aerospace, and industrial maintenance where a strong, reusable 1/4"-28 fine thread is needed.

What are the specifications of the HELI-COIL 1191-4CN375S insert?

This HELI-COIL insert is free-running, tanged tang style, with a 1/4"-28 fine thread, right-hand orientation, and plain finish. It is made from 18-8 metal with tensile strength of 200,000 to 250,000 psi, supplied in a 1,000-piece pack.

Where to buy HELI-COIL helical inserts worldwide?

3G Electric supplies HELI-COIL helical inserts worldwide, handling full logistics and customs clearance. We source genuine industrial parts across 14 departments, including fasteners and thread repair, and deliver to global destinations without requiring local warehousing.

How to install a tanged HELI-COIL insert?

To install a tanged HELI-COIL insert, drill to the specified tap drill size, tap the hole with the correct HELI-COIL tap, then use a tang break-off tool to insert the coil. After installation, remove the tang with a punch. Always follow the manufacturer's instructions for torque and depth.

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 tanged 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: Tanged Tang Style, Free-Running, 1/2"-14 Thread Size, Plain, Plain, 5 PK (MPN K327-8). Key specifications — attr798694: 18-8; attr798710: Right Hand; attr798707: 1/2"-14; attr798676: Metal; attr798705: Inch; attr798675: HELI-COIL; attr798708: 200,000 to 250,000 psi; attr798713: ANPT.
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HELI-COIL Helical Insert: Tanged Tang Style, Free-Running, 1/2"-14 Thread Size, Plain, Plain, 5 PK (MPN K327-8). Key specifications — attr798694: 18-8; attr798710: Right Hand; attr798707: 1/2"-14; attr798676: Metal; attr798705: Inch; attr798675: HELI-COIL; attr798708: 200,000 to 250,000 psi; attr798713: ANPT.
HELI-COIL Helical Insert: Tanged Tang Style, Free-Running, #10-32 Thread Size, Plain, Plain, 100 PK (MPN A1191-3CN380). Key specifications — attr798694: 18-8; attr798710: Right Hand; attr798707: #10-32; attr798676: Metal; attr798705: Inch; attr798675: HELI-COIL; attr798708: 200,000 to 250,000 psi; attr798713: Fine.
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HELI-COIL Helical Insert: Tanged Tang Style, Free-Running, #10-32 Thread Size, Plain, Plain, 100 PK (MPN A1191-3CN380). Key specifications — attr798694: 18-8; attr798710: Right Hand; attr798707: #10-32; attr798676: Metal; attr798705: Inch; attr798675: HELI-COIL; attr798708: 200,000 to 250,000 psi; attr798713: Fine.
HELI-COIL Helical Insert: Tanged Tang Style, Free-Running, #4-40 Thread Size, 100 PK (MPN A1185-04CNW224). Key specifications — attr798694: 18-8; attr798710: Right Hand; attr798707: #4-40; attr798676: Metal; attr798705: Inch; attr798675: HELI-COIL; attr798708: 200,000 to 250,000 psi; attr798713: Coarse.
HELI-COIL
HELI-COIL Helical Insert: Tanged Tang Style, Free-Running, #4-40 Thread Size, 100 PK (MPN A1185-04CNW224). Key specifications — attr798694: 18-8; attr798710: Right Hand; attr798707: #4-40; attr798676: Metal; attr798705: Inch; attr798675: HELI-COIL; attr798708: 200,000 to 250,000 psi; attr798713: Coarse.
HELI-COIL Helical Insert: Tanged Tang Style, Free-Running, 1/4"-28 Thread Size, Plain, Plain, 100 PK (MPN A1191-4CN375). Key specifications — attr798694: 18-8; attr798710: Right Hand; attr798707: 1/4"-28; attr798676: Metal; attr798705: Inch; attr798675: HELI-COIL; attr798708: 200,000 to 250,000 psi; attr798713: Fine.
HELI-COIL
HELI-COIL Helical Insert: Tanged Tang Style, Free-Running, 1/4"-28 Thread Size, Plain, Plain, 100 PK (MPN A1191-4CN375). Key specifications — attr798694: 18-8; attr798710: Right Hand; attr798707: 1/4"-28; attr798676: Metal; attr798705: Inch; attr798675: HELI-COIL; attr798708: 200,000 to 250,000 psi; attr798713: Fine.
HELI-COIL Helical Insert: Tanged Tang Style, Free-Running, #5-40 Thread Size, Stainless Steel, 12 PK (MPN R1185-05). Key specifications — attr798694: 18-8; attr798710: Right Hand; attr798707: #5-40; attr798676: Metal; attr798705: Inch; attr798675: HELI-COIL; attr798708: 200,000 to 250,000 psi; attr798713: Coarse.
HELI-COIL
HELI-COIL Helical Insert: Tanged Tang Style, Free-Running, #5-40 Thread Size, Stainless Steel, 12 PK (MPN R1185-05). Key specifications — attr798694: 18-8; attr798710: Right Hand; attr798707: #5-40; attr798676: Metal; attr798705: Inch; attr798675: HELI-COIL; attr798708: 200,000 to 250,000 psi; attr798713: Coarse.
HELI-COIL Helical Insert: Tanged Tang Style, Free-Running, M18-2.50 Thread Size, Plain, Plain, 6 PK (MPN R1084-18). Key specifications — attr798694: 18-8; attr798710: Right Hand; attr798707: M18-2.50; attr798676: Metal; attr798705: Metric; attr798675: HELI-COIL; attr798708: 200,000 to 250,000 psi; attr798713: Coarse.
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HELI-COIL Helical Insert: Tanged Tang Style, Free-Running, M18-2.50 Thread Size, Plain, Plain, 6 PK (MPN R1084-18). Key specifications — attr798694: 18-8; attr798710: Right Hand; attr798707: M18-2.50; attr798676: Metal; attr798705: Metric; attr798675: HELI-COIL; attr798708: 200,000 to 250,000 psi; attr798713: Coarse.
HELI-COIL Helical Insert: Tanged Tang Style, Free-Running, 1/4"-20 Thread Size, Plain, Plain, 100 PK (MPN A1185-4CN500). Key specifications — attr798694: 18-8; attr798710: Right Hand; attr798707: 1/4"-20; attr798676: Metal; attr798705: Inch; attr798675: HELI-COIL; attr798708: 200,000 to 250,000 psi; attr798713: Coarse.
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HELI-COIL Helical Insert: Tanged Tang Style, Free-Running, 1/4"-20 Thread Size, Plain, Plain, 100 PK (MPN A1185-4CN500). Key specifications — attr798694: 18-8; attr798710: Right Hand; attr798707: 1/4"-20; attr798676: Metal; attr798705: Inch; attr798675: HELI-COIL; attr798708: 200,000 to 250,000 psi; attr798713: Coarse.
HELI-COIL Helical Insert: Tanged Tang Style, Free-Running, 5/8"-11 Thread Size, Plain, Plain, 6 PK (MPN R1185-10). Key specifications — attr798694: 18-8; attr798710: Right Hand; attr798707: 5/8"-11; attr798676: Metal; attr798705: Inch; attr798675: HELI-COIL; attr798708: 200,000 to 250,000 psi; attr798713: Coarse.
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HELI-COIL Helical Insert: Tanged Tang Style, Free-Running, 5/8"-11 Thread Size, Plain, Plain, 6 PK (MPN R1185-10). Key specifications — attr798694: 18-8; attr798710: Right Hand; attr798707: 5/8"-11; attr798676: Metal; attr798705: Inch; attr798675: HELI-COIL; attr798708: 200,000 to 250,000 psi; attr798713: Coarse.