OSG Screw Thread Insert STI Tap: Spiral Fute, 5/16"-18 UNC, H3 / 2B-3B

This OSG spiral-flute STI tap is designed for cutting internal threads in aluminum and other non-ferrous materials. It creates threads that accept screw thread inserts (STI), providing strong, wear-resistant threads in softer metals. Common applications include automotive, aerospace, and general manufacturing where thread repair or reinforcement is needed.

This OSG tap has a thread size of 5/16"-18 UNC, with a thread tolerance of H3 / 2B-3B. It features a spiral-flute design with 2 flutes, optimized for chip evacuation in aluminum. The manufacturer part number is 1303900800. It is a high-speed steel tap suitable for through-hole threading.

3G Electric supplies OSG STI taps worldwide. As a global industrial distributor, we handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead time. We source genuine OSG tooling to meet your production needs.

For aluminum, choose a spiral-flute STI tap like this OSG model to manage chip flow. Ensure the thread size (5/16"-18 UNC) matches your insert requirements. The H3 / 2B-3B tolerance provides a precise fit for standard inserts. Use proper cutting fluid and avoid excessive speed to extend tool life.