HELI-COIL Helical Insert: Tangless Tang Style, Free-Running, 1/4"-28 Thread Size
The HELI-COIL Helical Insert (Tangless Tang Style) is a free-running, plain finish insert with a 1/4"-28 fine thread, right-hand direction, and an STI tap size of #10-32. Made from 18-8 material grade/class, it…
SKU 3G-OTH-527330
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Product Description
The HELI-COIL Helical Insert (Tangless Tang Style) is a free-running, plain finish insert with a 1/4"-28 fine thread, right-hand direction, and an STI tap size of #10-32. Made from 18-8 material grade/class, it offers a tensile strength of 200,000 to 250,000 psi and is compatible with metal substrates. Supplied in a 100-pack (SKU 4GCV6, MPN AT1191-4C250), this inch-system insert is designed for thread repair and reinforcement in metal applications.
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 Tangless helical insert used for?
A HELI-COIL Tangless helical insert repairs or reinforces stripped or damaged internal threads in metal components. The tangless design eliminates the need for a break-off tang, simplifying installation. It is commonly used in automotive, aerospace, and industrial maintenance applications to restore thread integrity without replacing the parent material.
What are the specifications of the HELI-COIL AT1191-4C250 insert?
The HELI-COIL AT1191-4C250 is a free-running, plain finish insert with a 1/4\"-28 fine thread, right-hand direction, and STI tap size #10-32. Made from 18-8 material, it offers a tensile strength of 200,000 to 250,000 psi. It is supplied in a 100-pack and is compatible with metal substrates.
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, customs clearance, and delivery to your location. Contact us for pricing and lead time on the AT1191-4C250 or other HELI-COIL part numbers. We source genuine industrial equipment across 14 departments.
How to install a tangless helical insert?
To install a tangless helical insert, drill the hole to the specified STI tap size (#10-32 for this insert), tap the hole with the corresponding STI tap, then use a tangless installation tool to wind the insert into the threaded hole. No break-off tang removal is needed. Follow the manufacturer's instructions for proper depth and alignment.
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3G Electric supplies HELI-COIL free-running tangless helical inserts. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.









