HELI-COIL Helical Insert: Tanged Tang Style, Screw-Locking, 1/4"-28 Thread Size
The HELI-COIL Helical Insert is a tanged tang style, screw-locking insert in a 100-pack, with a 1/4"-28 fine thread, right-hand direction, and an 18-8 material grade. It features a dry film lubricant finish, a…
SKU 3G-OTH-528911
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Product Description
The HELI-COIL Helical Insert is a tanged tang style, screw-locking insert in a 100-pack, with a 1/4"-28 fine thread, right-hand direction, and an 18-8 material grade. It features a dry film lubricant finish, a tensile strength of 200,000 to 250,000 psi, and is compatible with metal substrates, requiring an STI tap size of 1/4"-28.
Supplied to the Philippines — compatible with 60 Hz installations. DHL Express delivery to Manila, Quezon City, Cebu, customs and duties handled door-to-door.
Frequently Asked Questions
What is a HELI-COIL helical insert used for?
A HELI-COIL helical insert repairs or reinforces threads in metal substrates, providing a durable, screw-locking thread for fasteners. It is commonly used in automotive, aerospace, and industrial maintenance to restore stripped threads or improve thread strength in aluminum or steel components.
What are the specifications of the HELI-COIL A3591-4CNW375 insert?
This HELI-COIL insert has a 1/4\"-28 fine thread, right-hand direction, and an 18-8 material grade. It offers a tensile strength of 200,000 to 250,000 psi, features a dry film lubricant finish, and requires an STI tap size of 1/4\"-28. It comes in a 100-pack with tanged tang style.
Where to buy HELI-COIL helical inserts worldwide?
3G Electric supplies HELI-COIL helical inserts worldwide, handling logistics, customs, and delivery to your location. As a global industrial solutions provider, we source genuine parts like the A3591-4CNW375 and ensure they reach you reliably, regardless of your country.
How to install a HELI-COIL screw-locking insert?
To install a HELI-COIL screw-locking insert, drill out the damaged thread to the specified size, tap the hole using the correct STI tap (1/4\"-28 for this insert), then wind the insert into the hole using a tang-style installation tool. Break off the tang after installation for a secure, locking thread.
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Common applications for HELI-COILHELI-COIL Products
3G Electric supplies HELI-COIL screw-locking tanged helical inserts. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.









