OSG Extension Tap: 5/16"-18 UNC, H3 / 2B-3B, 3 Flute, Plug Chamfer
The OSG Extension Tap (5/16"-18 UNC, MPN 1298400) is a spiral-flute extension tap with a plug chamfer, made from high-speed steel. It features an H3 / 2B-3B tolerance class and 3 flutes, designed for threading…
SKU 3G-OTH-310973
Local availability & support — Singapore
- Local office
- 20 Woodlands Link #09-05, Singapore 738733
- Phone
- +65 8878 8355
- Delivery
- Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
- Payment
- Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
- Ships to
- Singapore
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Product Description
The OSG Extension Tap (5/16"-18 UNC, MPN 1298400) is a spiral-flute extension tap with a plug chamfer, made from high-speed steel. It features an H3 / 2B-3B tolerance class and 3 flutes, designed for threading applications requiring extended reach.
Frequently Asked Questions
What is the OSG Extension Tap 5/16"-18 UNC used for?
The OSG Extension Tap is used for threading blind or deep holes in metalwork, particularly where standard taps cannot reach. Its spiral-flute design clears chips upward, making it ideal for automotive, aerospace, and general manufacturing applications requiring precise UNC threads.
What are the specifications of the OSG Extension Tap 1298400?
This OSG Extension Tap has a 5/16"-18 UNC thread size, H3 / 2B-3B tolerance, 3-flute design, and plug chamfer. It is made from high-speed steel (HSS) and is suitable for threading both 2B and 3B class holes. The manufacturer part number is 1298400.
Where to buy the OSG Extension Tap 5/16"-18 UNC worldwide?
You can source the OSG Extension Tap 5/16"-18 UNC worldwide through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead time.
How to select the correct OSG Extension Tap for threading?
To select the correct OSG Extension Tap, match the thread size (e.g., 5/16"-18 UNC), tolerance class (H3 / 2B-3B), and chamfer type (plug) to your application. For deep or blind holes, choose a spiral-flute tap like this OSG model to evacuate chips. Always verify material compatibility with high-speed steel.
Used in
Common applications for OSGOSG Products
3G Electric supplies OSG spiral-flute extension taps. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.
