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3G Electric
OSG 1/4"-20 UNC Spiral-Flute Extension Tap - Spiral-Flute Extension Taps
OSGSpiral-Flute Extension Taps

OSG 1/4"-20 UNC Spiral-Flute Extension Tap

The OSG Extension Tap (1/4"-20 UNC, MPN 1298000) is a spiral-flute 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…

SKU 3G-OTH-310986

Brand
OSG
Item
1/4"-20 UNC Spiral-Flute Extension Tap
Part Number
1298000
Category
Spiral-Flute Extension Taps
Available to Order
Also known as:1298000OSG
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Local office
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Phone
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Technical Specifications

OSG
Manufacturer Part Number
1298000
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 (1/4"-20 UNC, MPN 1298000) is a spiral-flute 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 1/4"-20 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 evacuates 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 MPN 1298000?

This OSG Extension Tap has a 1/4"-20 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 fits. The manufacturer part number is 1298000.

Where to buy the OSG Extension Tap 1298000 worldwide?

You can source the OSG Extension Tap 1298000 through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations. Contact us for availability and lead time on this OSG brand tap.

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

Select the OSG extension tap based on thread size (e.g., 1/4"-20 UNC), material (HSS for general steel), and hole depth. The plug chamfer suits through or blind holes. Ensure the H3 tolerance matches your required thread class (2B or 3B). Consult OSG's technical data for optimal feed and speed.

Used in

Common applications for OSG
Aerospace — OSG STI taps for installing helical wire thread inserts in aluminum components
Automotive — OSG spiral-point taps for through-hole threading in engine blocks and transmission cases
General machining — OSG spiral-flute taps for blind-hole threading in steel and stainless steel parts
Heavy equipment repair — OSG thread-forming taps for creating threads in ductile iron and steel castings
Precision manufacturing — OSG solid carbide chucking reamers for finishing holes in hydraulic manifolds
Die and mold — OSG coolant-through solid carbide drills for deep-hole drilling in tool steels
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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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