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OSG Extension Tap: 3/8"-16 UNC, H3 / 2B-3B, 4 Flute, Plug Chamfer - Pulley Taps
OSGPulley Taps

OSG Extension Tap: 3/8"-16 UNC, H3 / 2B-3B, 4 Flute, Plug Chamfer

The OSG Extension Tap (MPN 1291001) is a 3/8"-16 UNC pulley tap with a H3 / 2B-3B tolerance, 4-flute design, plug chamfer, and black oxide high-speed steel construction. 3G Electric interprets this demand and sources…

SKU 3G-OTH-308214

Brand
OSG
Item
Extension Tap: 3/8"-16 UNC, H3 / 2B-3B, 4 Flute, Plug Chamfer
Category
Pulley Taps
Available to Order
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Technical Specifications

OSG
Manufacturer Part Number
1291001
Type
H3 / 2B-3B, Plug Chamfer, Black Oxide High Speed Steel
Flute
4
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OSG Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The OSG Extension Tap (MPN 1291001) is a 3/8"-16 UNC pulley tap with a H3 / 2B-3B tolerance, 4-flute design, plug chamfer, and black oxide high-speed steel construction. 3G Electric interprets this demand and sources the genuine OEM tool, supporting your machining operations across 14 industrial departments — with specialist depth in cutting tools and controls.

Frequently Asked Questions

What is the OSG Extension Tap 1291001 used for?

The OSG Extension Tap 1291001 is a pulley tap designed for threading blind holes in pulleys and other hard-to-reach areas. Its extended length allows access to deep or recessed threads. Common applications include automotive, machinery, and general industrial maintenance where UNC threads are required.

What are the specifications of the OSG Extension Tap 1291001?

This OSG tap has a 3/8"-16 UNC thread size with H3 / 2B-3B tolerance class. It features a 4-flute design with plug chamfer and is made from black oxide high-speed steel. The manufacturer part number is 1291001. It is suitable for threading both 2B and 3B class holes.

Where to buy the OSG Extension Tap 1291001 worldwide?

You can source the OSG Extension Tap 1291001 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; we provide competitive pricing and reliable sourcing for this pulley tap.

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

To select the correct OSG extension tap, match the thread size (e.g., 3/8"-16 UNC) and tolerance class (H3 / 2B-3B) to your hole requirements. Consider the material being threaded—high-speed steel works for most metals. Ensure the tap length reaches the thread depth. For blind holes, a plug chamfer is standard.

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

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