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HELI-COIL Helical Insert: Tangless Tang Style, Screw-Locking, 1/4"-28 Thread Size - Screw-Locking Tangless Helical Inserts
HELI-COILScrew-Locking Tangless Helical Inserts

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

HELI-COIL Tangless Tang Style Helical Insert, a screw-locking tangless insert with 1/4"-28 fine thread, 18-8 material grade, and dry film lubricant finish. Supplied in a 100-piece pack (MPN AT3591-4CW375), it offers…

SKU 3G-OTH-532475

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

HELI-COIL
Manufacturer Part Number
AT3591-4CW375
Type
Screw-Locking, 100 PK
Tensile Strength
200,000 to 250,000 psi
Finish Type
Dry Film Lubricant
Thread Size
1/4"-28
Thread Type
Fine
STI Tap Size
1/4"-28
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

HELI-COIL Tangless Tang Style Helical Insert, a screw-locking tangless insert with 1/4"-28 fine thread, 18-8 material grade, and dry film lubricant finish. Supplied in a 100-piece pack (MPN AT3591-4CW375), it offers a tensile strength of 200,000 to 250,000 psi for metal-compatible, right-hand thread applications.

Frequently Asked Questions

What is a HELI-COIL Tangless Tang Style helical insert used for?

A HELI-COIL Tangless Tang Style helical insert repairs or reinforces tapped threads in metal. The screw-locking version resists vibration loosening. The tangless design eliminates the need to break off a tang after installation, saving time in production and maintenance applications.

What are the specifications of the HELI-COIL AT3591-4CW375 insert?

The HELI-COIL AT3591-4CW375 is a screw-locking tangless insert with 1/4\"-28 fine thread, 18-8 material grade, and dry film lubricant finish. It has a tensile strength of 200,000 to 250,000 psi, is compatible with metal, and comes in a 100-piece pack.

Where to buy HELI-COIL helical inserts in worldwide?

3G Electric supplies HELI-COIL helical inserts worldwide. As a global industrial solutions provider, we handle full logistics and customs clearance to deliver the AT3591-4CW375 and other HELI-COIL products to your facility. Contact us for a quote and delivery timeline.

How to install a tangless helical insert?

To install a tangless helical insert, drill and tap the hole to the STI tap size (1/4\"-28 for this insert). Use a tangless installation tool to wind the insert into the tapped hole until it sits slightly below the surface. No tang removal step 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 screw-locking 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, Screw-Locking, #10-32 Thread Size, 100 PK (MPN AT3591-3CW190). 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, Screw-Locking, #2-56 Thread Size, Plain, 100 PK (MPN AT3585-02C086). 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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HELI-COIL Helical Insert: Tangless Tang Style, Screw-Locking, #6-32 Thread Size, Plain, 100 PK (MPN AT3585-06C138). 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, Screw-Locking, #6-32 Thread Size, Plain, 100 PK (MPN AT3585-06C138). 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, Screw-Locking, #8-32 Thread Size, Plain, 1,000 PK (MPN T3585-2C246S). Key specifications — Material Grade/Class: 18-8; Thread Direction: Right Hand; STI Tap Size: #8-32; 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, Screw-Locking, #4-40 Thread Size, 100 PK (MPN AT3585-04CW112). Key specifications — Material Grade/Class: 18-8; Thread Direction: Right Hand; STI Tap Size: #4-40; 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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