HELI-COIL Helical Insert: Tanged Tang Style, Screw-Locking, 3/4"-16 Thread Size
The HELI-COIL Helical Insert is a tanged tang style, screw-locking insert with a 3/4"-16 fine thread, 1 1/8 in overall length, and a tensile strength of 200,000 to 250,000 psi. Made from 18-8 material grade/class, it…
SKU 3G-OTH-528904
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Product Description
The HELI-COIL Helical Insert is a tanged tang style, screw-locking insert with a 3/4"-16 fine thread, 1 1/8 in overall length, and a tensile strength of 200,000 to 250,000 psi. Made from 18-8 material grade/class, it is compatible with metal and uses a right-hand thread direction. This inch-system insert requires an STI tap size of 3/4"-16 and has a plain finish.
Frequently Asked Questions
What is a HELI-COIL helical insert used for?
A HELI-COIL helical insert repairs or reinforces threads in metal components. This screw-locking, tanged tang style insert provides strong, wear-resistant threads in applications like automotive, aerospace, and industrial machinery where original threads are stripped or need added strength.
What are the specifications of the HELI-COIL 3591-12CN1125 insert?
This HELI-COIL insert has a 3/4"-16 fine thread, 1 1/8 in overall length, and tensile strength of 200,000 to 250,000 psi. It is made from 18-8 material, uses a right-hand thread direction, requires an STI tap size of 3/4"-16, and has a plain finish.
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 3/4"-16 screw-locking insert to your facility. Contact us for pricing and lead time on the 3591-12CN1125.
How to install a HELI-COIL tanged tang insert?
To install a HELI-COIL tanged tang insert, drill out the damaged thread to the specified size, tap the hole using the correct STI tap (3/4"-16 for this insert), then wind the insert into the tapped hole using a tang drive tool. After installation, break off the tang for a flush finish.
Used in
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.









