OSG Screw Thread Insert STI Tap: Spiral Fute, 5/16"-18 UNC, H3 / 2B-3B
SKU 3G-OTH-244397
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Frequently Asked Questions
What is an OSG Screw Thread Insert STI Tap used for?
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 automotive, aerospace, and heavy equipment repair where stripped threads must be restored without replacing the parent component.
What are the specifications of the OSG 30201201 STI Tap?
The OSG 30201201 is a spiral-flute STI tap with thread size 5/16"-18 UNC, 3 flutes, and tolerance class H3 / 2B-3B. It is designed for threading holes that will receive screw thread inserts in steel and stainless steel workpieces.
Where to buy OSG STI Taps worldwide?
3G Electric supplies OSG STI Taps worldwide. As a global industrial sourcing partner, we handle full logistics, customs clearance, and delivery to your facility. Contact us for pricing and lead time on the OSG 30201201 spiral-flute tap.
How to select the correct STI tap size for thread repair?
Select an STI tap that matches the original thread size and pitch, such as 5/16"-18 UNC. The tap tolerance (H3 / 2B-3B) must align with the insert manufacturer's recommendation. Always use the correct drill size for the STI tap to ensure proper thread engagement.
Used in
Common applications for OSGOSG Products
3G Electric supplies OSG spiral-flute sti taps for steel & stainless steel. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.















