HELI-COIL Thread Repair Kit: Tanged Tang Style, Free-Running, 1 1/4"-7 Thread Size
The HELI-COIL Thread Repair Kit (MPN 5521-20) is a tanged tang style insert and tool kit for repairing damaged threads in metal. It includes free-running, 18-8 stainless steel helical inserts with a coarse…
SKU 3G-OTH-527883
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Product Description
The HELI-COIL Thread Repair Kit (MPN 5521-20) is a tanged tang style insert and tool kit for repairing damaged threads in metal. It includes free-running, 18-8 stainless steel helical inserts with a coarse, right-hand thread size of 1 1/4"-7 (inch system). The kit comes with an STI tap of the same size, enabling restoration of original thread strength in metal components.
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 the HELI-COIL Thread Repair Kit 5521-20 used for?
The HELI-COIL Thread Repair Kit 5521-20 is used to restore damaged internal threads in metal components. It installs 18-8 stainless steel helical inserts to create a new, durable coarse thread of 1 1/4"-7, commonly applied in automotive, industrial machinery, and heavy equipment repairs.
What are the specifications of the HELI-COIL 5521-20 kit?
The HELI-COIL 5521-20 kit includes free-running, tanged tang style helical inserts made of 18-8 stainless steel. Thread size is 1 1/4"-7 coarse, right-hand, inch system. It comes with an STI tap of the same size, compatible with metal substrates. Manufacturer part number 5521-20.
Where to buy HELI-COIL Thread Repair Kit 5521-20 worldwide?
3G Electric supplies the HELI-COIL Thread Repair Kit 5521-20 to customers worldwide. As a global industrial solutions provider, we handle full logistics, customs clearance, and delivery to your location. Contact us for pricing and lead time on this thread repair kit.
How to install a HELI-COIL thread insert from kit 5521-20?
To install, drill out the damaged thread to the specified size, then tap the hole using the included STI tap. Insert the helical coil using the tang end, then break off the tang after installation. Ensure the hole is clean and lubricated for proper seating. Follow HELI-COIL instructions for torque values.
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3G Electric supplies HELI-COIL insert & tool kits. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.









