HELI-COIL Screw Thread Insert STI Tap: Straight Fute, M8x1 Metric, D9 / 4H, 4 Flute

A HELI-COIL STI tap cuts threads for installing screw thread inserts, commonly used to repair or reinforce stripped threads in metal, aluminum, and cast iron. It is ideal for automotive, aerospace, and industrial maintenance applications where thread strength and reliability are critical.

The HELI-COIL 5484-8 STI tap is M8x1 metric with a D9 / 4H tolerance, 4 straight flutes, and a plug chamfer. It is designed for general-purpose thread repair and insert installation, ensuring accurate thread pitch and fit for M8 inserts.

3G Electric supplies HELI-COIL STI taps worldwide, handling full logistics and customs clearance. As a global industrial sourcing partner, we provide genuine HELI-COIL taps like the 5484-8 to customers across 14 departments, including machining and maintenance. Contact us for availability and delivery.

Select an STI tap that matches the insert thread size and pitch, such as M8x1 for HELI-COIL inserts. Ensure the tap tolerance (e.g., D9 / 4H) aligns with the required thread class. Use a plug chamfer for through holes or blind holes with sufficient depth. Always follow the insert manufacturer’s recommendations.