OSG Screw Thread Insert STI Tap: Spiral Fute, 7/8"-14 UNF, H3 / 2B-3B

An OSG Screw Thread Insert STI Tap cuts internal threads in steel and stainless steel to accept helical wire thread inserts. It is commonly used in aerospace, automotive, and heavy equipment repair where stripped threads must be restored to original strength without replacing the parent component.

The OSG 30205601 is a spiral-flute STI tap with a 7/8"-14 UNF thread, H3 / 2B-3B tolerance, and 4 flutes. It is designed for threading holes that will receive screw thread inserts in steel and stainless steel. The spiral flute design aids chip evacuation in blind-hole applications.

3G Electric supplies OSG STI Taps like the 30205601 to customers worldwide. We handle full logistics, customs clearance, and delivery to your facility. Contact us for a quote on this or any OSG threading tool — we source genuine industrial equipment across 14 departments and deliver globally.

Select an STI tap that matches the original thread size and pitch — for example, 7/8"-14 UNF. The tap must be marked for screw thread insert use (STI) and have the correct tolerance class (H3 for 2B-3B fit). Always verify the insert manufacturer's recommended drill size and tap specifications before cutting.