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OSG Extension Tap: 5/8"-11 UNC, H3 / 2B-3B, 4 Flute, Bottoming Chamfer - Spiral-Flute Extension Taps
OSGSpiral-Flute Extension Taps

OSG Extension Tap: 5/8"-11 UNC, H3 / 2B-3B, 4 Flute, Bottoming Chamfer

The OSG Extension Tap (MPN 1299300) is a 5/8"-11 UNC spiral-flute extension tap, type H3 / 2B-3B with a bottoming chamfer, made of high-speed steel and featuring 4 flutes. 3G Electric interprets your demand for this…

SKU 3G-OTH-310969

Brand
OSG
Item
Extension Tap: 5/8"-11 UNC, H3 / 2B-3B, 4 Flute, Bottoming Chamfer
Category
Spiral-Flute Extension Taps
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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
1299300
Type
H3 / 2B-3B, Bottoming Chamfer, High Speed Steel
Flute
4

Technical Documents

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

Product Description

The OSG Extension Tap (MPN 1299300) is a 5/8"-11 UNC spiral-flute extension tap, type H3 / 2B-3B with a bottoming chamfer, made of high-speed steel and featuring 4 flutes. 3G Electric interprets your demand for this precision threading tool, sources it from OSG, and supports your application with specialist expertise across 14 industrial departments.

Frequently Asked Questions

What is an OSG extension tap used for?

An OSG extension tap is used to cut internal threads in deep or hard-to-reach holes. The 5/8"-11 UNC bottoming chamfer design allows threading to the bottom of a blind hole, common in automotive, aerospace, and general machining applications.

What are the specifications of the OSG 1299300 extension tap?

The OSG 1299300 is a 5/8"-11 UNC spiral-flute extension tap with a bottoming chamfer, 4 flutes, and H3 / 2B-3B tolerance. It is made of high-speed steel (HSS) and is designed for threading blind holes in ferrous and non-ferrous materials.

Where to buy OSG extension taps worldwide?

3G Electric supplies OSG extension taps worldwide. We handle full logistics, customs clearance, and delivery to your facility. As a global industrial solutions provider, we source genuine OSG tooling and support your procurement with technical expertise across 14 industrial departments.

How to select the correct OSG extension tap for a blind hole?

Select an OSG extension tap with a bottoming chamfer for blind holes, as it threads close to the bottom. Match the thread size (5/8"-11 UNC), flute count (4), and tolerance class (H3 / 2B-3B) to your application. Use high-speed steel for general-purpose threading in steel and cast iron.

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. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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Cross-referenced by specification & description
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OSG Extension Tap: #10-32 UNF, H3 / 2B-3B, 3 Flute, Bottoming Chamfer, High Speed Steel (MPN 1297500)
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OSG Extension Tap: #10-32 UNF, H3 / 2B-3B, 3 Flute, Bottoming Chamfer, High Speed Steel (MPN 1297500)
OSG Extension Tap: #6-32 UNC, H3 / 2B-3B, 2 Flute, Bottoming Chamfer, High Speed Steel (MPN 1296300)
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OSG Extension Tap: #6-32 UNC, H3 / 2B-3B, 2 Flute, Bottoming Chamfer, High Speed Steel (MPN 1296300)
OSG Extension Tap: 5/8"-11 UNC, H3 / 2B-3B, 4 Flute, Plug Chamfer, High Speed Steel (MPN 1299200)
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OSG Extension Tap: 5/8"-11 UNC, H3 / 2B-3B, 4 Flute, Plug Chamfer, High Speed Steel (MPN 1299200)
OSG Extension Tap: 1/4"-20 UNC, H3 / 2B-3B, 3 Flute, Bottoming Chamfer, High Speed Steel (MPN 1297900)
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OSG Extension Tap: 1/4"-20 UNC, H3 / 2B-3B, 3 Flute, Bottoming Chamfer, High Speed Steel (MPN 1297900)

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OSG Extension Tap: #8-32 UNC, H3 / 2B-3B, 3 Flute, Plug Chamfer, High Speed Steel (MPN 1296600)
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OSG Extension Tap: #8-32 UNC, H3 / 2B-3B, 3 Flute, Plug Chamfer, High Speed Steel (MPN 1296600)
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OSG Extension Tap: 1/4"-20 UNC, H3 / 2B-3B, 3 Flute, Plug Chamfer, High Speed Steel (MPN 1297800)
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OSG Extension Tap: #6-32 UNC, H3 / 2B-3B, 2 Flute, Plug Chamfer, High Speed Steel (MPN 1296200)
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OSG Extension Tap: #10-24 UNC, H3 / 2B-3B, 3 Flute, Bottoming Chamfer, High Speed Steel (MPN 1297100)
OSG Extension Tap: #10-32 UNF, H3 / 2B-3B, 3 Flute, Plug Chamfer, High Speed Steel (MPN 1297600)
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OSG Extension Tap: #10-32 UNF, H3 / 2B-3B, 3 Flute, Plug Chamfer, High Speed Steel (MPN 1297600)
OSG Extension Tap: 3/8"-16 UNC, H3 / 2B-3B, 3 Flute, Bottoming Chamfer, High Speed Steel (MPN 1298700)
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OSG Extension Tap: 3/8"-16 UNC, H3 / 2B-3B, 3 Flute, Bottoming Chamfer, High Speed Steel (MPN 1298700)
OSG Extension Tap: 7/16"-14 UNC, H3 / 2B-3B, 3 Flute, Plug Chamfer, High Speed Steel (MPN 1298800)
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OSG Extension Tap: 7/16"-14 UNC, H3 / 2B-3B, 3 Flute, Plug Chamfer, High Speed Steel (MPN 1298800)