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OSG Extension Tap: 5/16"-18 UNC, H3 / 2B-3B, 4 Flute, Plug Chamfer - Pulley Taps
OSGPulley Taps

OSG Extension Tap: 5/16"-18 UNC, H3 / 2B-3B, 4 Flute, Plug Chamfer

The OSG Extension Tap (MPN 1290401) is a 5/16"-18 UNC pulley tap with a H3 / 2B-3B tolerance, 4-flute design, plug chamfer, and black oxide high-speed steel construction. This tool is designed for threading…

SKU 3G-OTH-308153

Brand
OSG
Item
Extension Tap: 5/16"-18 UNC, H3 / 2B-3B, 4 Flute, Plug Chamfer
Category
Pulley Taps
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Technical Specifications

OSG
Manufacturer Part Number
1290401
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 1290401) is a 5/16"-18 UNC pulley tap with a H3 / 2B-3B tolerance, 4-flute design, plug chamfer, and black oxide high-speed steel construction. This tool is designed for threading applications requiring extended reach.

Frequently Asked Questions

What is the OSG Extension Tap 1290401 used for?

The OSG Extension Tap 1290401 is used for threading blind or deep holes in industrial applications, particularly for pulley assemblies. Its extended reach allows access to recessed areas, and the 5/16"-18 UNC thread size suits standard fasteners in automotive and machinery maintenance.

What are the specifications of the OSG Extension Tap 1290401?

The OSG Extension Tap 1290401 has a 5/16"-18 UNC thread, H3 / 2B-3B tolerance, 4 flute design, and plug chamfer. It is made of black oxide high-speed steel for durability. The manufacturer part number is 1290401, and it is classified as a pulley tap for extended-reach threading.

Where to buy the OSG Extension Tap 1290401 worldwide?

You can source the OSG Extension Tap 1290401 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 reliable sourcing for this OSG pulley tap.

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

To select the correct OSG extension tap, match the thread size (e.g., 5/16"-18 UNC) and tolerance (H3 / 2B-3B) to your hole requirements. Consider the tap's reach for deep or blind holes, and choose a plug chamfer for general threading. OSG's black oxide high-speed steel offers good wear resistance for manual or machine use.

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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