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OSG Extension Tap: 1/2"-13 UNC, H3 / 2B-3B, 3 Flute, Plug Chamfer - Spiral-Point Extension Taps
OSGSpiral-Point Extension Taps

OSG Extension Tap: 1/2"-13 UNC, H3 / 2B-3B, 3 Flute, Plug Chamfer

The OSG Extension Tap (MPN 1295500) is a 1/2"-13 UNC spiral-point extension tap with H3 / 2B-3B tolerance, 3 flutes, plug chamfer, and high-speed steel construction. 3G Electric sources this precision threading tool…

SKU 3G-OTH-313570

Brand
OSG
Item
Extension Tap: 1/2"-13 UNC, H3 / 2B-3B, 3 Flute, Plug Chamfer
Category
Spiral-Point Extension Taps
Available to Order
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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
1295500
Type
H3 / 2B-3B, Plug Chamfer, High Speed Steel
Flute
3

Technical Documents

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

Product Description

The OSG Extension Tap (MPN 1295500) is a 1/2"-13 UNC spiral-point extension tap with H3 / 2B-3B tolerance, 3 flutes, plug chamfer, and high-speed steel construction. 3G Electric sources this precision threading tool as part of our industrial supply across 14 departments, with specialist expertise in combustion, pumps, and controls ensuring accurate sourcing and support.

Frequently Asked Questions

What is the OSG Extension Tap 1/2"-13 UNC used for?

This OSG extension tap is used for threading blind or through holes in metal parts where a standard tap cannot reach. It is common in automotive, aerospace, and general manufacturing for creating internal UNC threads with a plug chamfer and spiral-point design.

What are the specifications of the OSG Extension Tap MPN 1295500?

The OSG Extension Tap has a 1/2"-13 UNC thread size, H3 / 2B-3B tolerance, 3-flute spiral-point design, and plug chamfer. It is made of high-speed steel (HSS) and is suitable for through-hole threading in steel and other materials.

Where to buy the OSG Extension Tap 1/2"-13 UNC worldwide?

You can source the OSG Extension Tap MPN 1295500 worldwide through 3G Electric. We handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead time; we supply genuine OSG tooling globally.

How to select the correct OSG extension tap for a job?

Select an OSG extension tap based on thread size (e.g., 1/2"-13 UNC), material (HSS for general steel), chamfer type (plug for through holes), and flute count (3-flute for chip evacuation). Match the H3 / 2B-3B tolerance to your required thread class.

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-point 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
OSG Extension Tap: 5/8"-11 UNC, H3 / 2B-3B, 3 Flute, Plug Chamfer, High Speed Steel (MPN 1295600)
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OSG Extension Tap: 1/4"-20 UNC, H3 / 2B-3B, 2 Flute, Plug Chamfer, High Speed Steel (MPN 1295000)
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OSG Extension Tap: 1/4"-20 UNC, H3 / 2B-3B, 2 Flute, Plug Chamfer, High Speed Steel (MPN 1295000)
OSG Extension Tap: 1/4"-20 UNC, H3 / 2B-3B, 2 Flute, Plug Chamfer, High Speed Steel (MPN 1294900)
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OSG Extension Tap: 1/4"-20 UNC, H3 / 2B-3B, 2 Flute, Plug Chamfer, High Speed Steel (MPN 1294900)
OSG Extension Tap: #10-32 UNF, H3 / 2B-3B, 2 Flute, Plug Chamfer, High Speed Steel (MPN 1294700)
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OSG Extension Tap: #10-32 UNF, H3 / 2B-3B, 2 Flute, Plug Chamfer, High Speed Steel (MPN 1294700)
OSG Extension Tap: 1/2"-13 UNC, H3 / 2B-3B, 3 Flute, Plug Chamfer, High Speed Steel (MPN 1299000)
OSG
OSG Extension Tap: 1/2"-13 UNC, H3 / 2B-3B, 3 Flute, Plug Chamfer, High Speed Steel (MPN 1299000)
OSG Extension Tap: 1/2"-20 UNF, H3 / 2B-3B, 3 Flute, Plug Chamfer, High Speed Steel (MPN 2106000)
OSG
OSG Extension Tap: 1/2"-20 UNF, H3 / 2B-3B, 3 Flute, Plug Chamfer, High Speed Steel (MPN 2106000)

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OSG Extension Tap: #6-32 UNC, H3 / 2B-3B, 2 Flute, Plug Chamfer, High Speed Steel (MPN 1294100)
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OSG Extension Tap: #8-32 UNC, H3 / 2B-3B, 2 Flute, Plug Chamfer, High Speed Steel (MPN 1294300)
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OSG Extension Tap: #8-32 UNC, H3 / 2B-3B, 2 Flute, Plug Chamfer, High Speed Steel (MPN 1294300)