OSG Screw Thread Insert STI Tap: Spiral Point, 7/8"-14 UNF, H4 / 2B-3B, 4 Flute
The OSG Screw Thread Insert STI Tap is a spiral-point tap designed for threading multiple materials, featuring a 7/8"-14 UNF thread size, H4 / 2B-3B tolerance, 4 flutes, and a plug chamfer (MPN 31403908).
SKU 3G-OTH-284688
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Product Description
The OSG Screw Thread Insert STI Tap is a spiral-point tap designed for threading multiple materials, featuring a 7/8"-14 UNF thread size, H4 / 2B-3B tolerance, 4 flutes, and a plug chamfer (MPN 31403908).
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 multiple materials to accept helical wire thread inserts. It is commonly used in aerospace, automotive, and industrial maintenance applications where stripped threads must be repaired or reinforced with a threaded insert.
What are the specifications of the OSG STI Tap 31403908?
The OSG STI Tap 31403908 is a spiral-point, plug-chamfer tap with 4 flutes. It cuts a 7/8"-14 UNF thread and is ground to H4 / 2B-3B tolerance class. This tap is designed for use with screw thread inserts in multiple materials.
Where to buy OSG STI Tap 31403908 worldwide?
3G Electric supplies the OSG STI Tap 31403908 to customers worldwide. We handle full logistics, customs clearance, and delivery to your site. Contact us for a quote and lead time on this spiral-point tap for thread insert applications.
How to select the correct STI tap for a thread insert?
Select an STI tap that matches the thread size and pitch of the insert, such as 7/8"-14 UNF. Use a plug-chamfer tap for through holes and a bottoming-chamfer for blind holes. The H4 tolerance ensures proper fit for 2B-3B class threads in the parent material.
Used in
Common applications for OSGOSG Products
3G Electric supplies OSG spiral-point sti taps for multiple materials. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.















