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OSG Extension Tap: 1/4"-28 UNF, H3 / 2B-3B, 3 Flute, Plug Chamfer - Spiral-Flute Extension Taps
OSGSpiral-Flute Extension Taps

OSG Extension Tap: 1/4"-28 UNF, H3 / 2B-3B, 3 Flute, Plug Chamfer

The OSG Extension Tap (MPN 1298200) is a 1/4"-28 UNF spiral-flute extension tap, type H3 / 2B-3B with a plug chamfer, made of high-speed steel and featuring 3 flutes. 3G Electric sources this precision threading tool…

SKU 3G-OTH-310984

Brand
OSG
Item
Extension Tap: 1/4"-28 UNF, H3 / 2B-3B, 3 Flute, Plug Chamfer
Category
Spiral-Flute Extension Taps
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Technical Specifications

OSG
Manufacturer Part Number
1298200
Type
H3 / 2B-3B, Plug Chamfer, High Speed Steel
Flute
3
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OSG Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The OSG Extension Tap (MPN 1298200) is a 1/4"-28 UNF spiral-flute extension tap, type H3 / 2B-3B with a plug chamfer, made of high-speed steel and featuring 3 flutes. 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 1/4"-28 UNF used for?

This OSG extension tap is designed for threading blind holes in hard-to-reach areas. Its spiral-flute design evacuates chips upward, making it ideal for automotive, aerospace, and general manufacturing applications where extended reach and precise UNF threads are required.

What are the specifications of the OSG Extension Tap 1298200?

The OSG Extension Tap (MPN 1298200) has a 1/4"-28 UNF thread size, H3 / 2B-3B tolerance, 3 flutes, and a plug chamfer. It is made from high-speed steel and is classified as a spiral-flute extension tap for threading blind holes.

Where to buy the OSG Extension Tap 1/4"-28 UNF worldwide?

You can source the OSG Extension Tap 1/4"-28 UNF worldwide through 3G Electric. As a global industrial equipment distributor since 1990, 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 UNF threads?

Select an OSG extension tap by matching the thread size (e.g., 1/4"-28 UNF), chamfer type (plug for blind holes), flute count (3 for chip evacuation), and tolerance class (H3 for 2B-3B fit). Ensure the tap length reaches your hole depth. OSG high-speed steel taps suit general-purpose threading.

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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