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OSG Extension Tap: #4-40 UNC, H2 / 2B-3B, 3 Flute - Spiral-Flute Extension Taps for Steel & Stainless Steel
OSGSpiral-Flute Extension Taps for Steel & Stainless Steel

OSG Extension Tap: #4-40 UNC, H2 / 2B-3B, 3 Flute

OSG Spiral-Flute Extension Taps for Steel & Stainless Steel.

SKU 3G-OTH-315318

Brand
OSG
Item
Extension Tap: #4-40 UNC, H2 / 2B-3B, 3 Flute
Category
Spiral-Flute Extension Taps for Steel & Stainless Steel
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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

Technical Specifications

OSG
Manufacturer Part Number
0143701

Technical Documents

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OSG Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

OSG Spiral-Flute Extension Taps for Steel & Stainless Steel.

Frequently Asked Questions

What is OSG extension tap #4-40 UNC used for?

This OSG extension tap is designed for threading blind holes in steel and stainless steel. Its spiral-flute design evacuates chips upward, while the bottoming chamfer allows threading close to the hole bottom. It is commonly used in automotive, aerospace, and general machining applications.

What are the specifications of OSG extension tap #4-40 UNC?

This OSG extension tap has a #4-40 UNC thread size, H2 / 2B-3B tolerance, 3 flutes, and a bottoming chamfer. The manufacturer part number is 0143701. It is a spiral-flute extension tap designed for steel and stainless steel, enabling deep or hard-to-reach hole threading.

Where to buy OSG extension tap #4-40 UNC worldwide?

3G Electric supplies and delivers OSG extension taps worldwide. As a global industrial solutions provider, we handle full logistics and customs clearance to ensure reliable delivery. Contact us for availability and lead time on this OSG #4-40 UNC extension tap.

How to select the correct OSG extension tap for steel?

For steel threading, choose an OSG extension tap with spiral flutes for chip evacuation and a bottoming chamfer for blind holes. Verify thread size (e.g., #4-40 UNC), tolerance class (H2 / 2B-3B), and material compatibility. Always match the tap to the hole depth and machine capability.

Used in

Common applications for OSG
Automotive engine block production — OSG micro drill bits for oil gallery and coolant passage drilling in cast iron
Medical device manufacturing — OSG micro drill bits for drilling bone screw pilot holes in stainless steel implants
Aerospace component machining — OSG micro drill bits for fastener holes in titanium alloy structural parts
Mold and die making — OSG micro drill bits for cooling channel drilling in hardened tool steel (HRC 45-50)
Electronics enclosure fabrication — OSG micro drill bits for precision holes in aluminum alloy housings (with appropriate coating selection)
General engineering job shops — OSG micro drill bits for small-diameter hole drilling in mild steel and alloy steel parts

OSG Products

3G Electric supplies OSG spiral-flute extension taps for steel & stainless steel. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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Compatible alternatives & equivalents

Cross-referenced by specification & description
OSG Extension Tap: #6-32 UNC, H3 / 2B-3B, 3 Flute, Bottoming Chamfer (MPN 0143801)
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OSG Extension Tap: #6-32 UNC, H3 / 2B-3B, 3 Flute, Bottoming Chamfer (MPN 0143801)
OSG Extension Tap: 1/4"-20 UNC, H3 / 2B-3B, 3 Flute, Bottoming Chamfer (MPN 0144101)
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OSG Extension Tap: 1/4"-20 UNC, H3 / 2B-3B, 3 Flute, Bottoming Chamfer (MPN 0144101)
OSG Extension Tap: 3/8"-16 UNC, H3 / 2B-3B, 3 Flute, Bottoming Chamfer (MPN 0144401)
OSG
OSG Extension Tap: 3/8"-16 UNC, H3 / 2B-3B, 3 Flute, Bottoming Chamfer (MPN 0144401)
OSG Extension Tap: 5/16"-18 UNC, H3 / 2B-3B, 3 Flute, Bottoming Chamfer (MPN 0144301)
OSG
OSG Extension Tap: 5/16"-18 UNC, H3 / 2B-3B, 3 Flute, Bottoming Chamfer (MPN 0144301)
OSG Extension Tap: 7/16"-14 UNC, H3 / 2B-3B, 3 Flute, Bottoming Chamfer (MPN 0144601)
OSG
OSG Extension Tap: 7/16"-14 UNC, H3 / 2B-3B, 3 Flute, Bottoming Chamfer (MPN 0144601)
OSG Extension Tap: #10-32 UNF, H3 / 2B-3B, 3 Flute, Bottoming Chamfer (MPN 0144001)
OSG
OSG Extension Tap: #10-32 UNF, H3 / 2B-3B, 3 Flute, Bottoming Chamfer (MPN 0144001)

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