OSG Extension Tap: 3/8"-16 UNC, H3 / 2B-3B, 4 Flute, Plug Chamfer
The OSG Extension Tap (MPN 1290801) 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. This tool is engineered for threading…
SKU 3G-OTH-308197
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Product Description
The OSG Extension Tap (MPN 1290801) 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. This tool is engineered for threading applications requiring extended reach, with its H3 / 2B-3B classification ensuring precise fit for class 2B-3B threads.
Frequently Asked Questions
What is an OSG extension tap used for?
An OSG extension tap is used to cut internal threads in hard-to-reach or deep-hole applications, such as pulley hubs or engine blocks. The extended shank allows threading where standard taps cannot reach, making it essential for maintenance and production in automotive, aerospace, and general machining.
What are the specifications of the OSG extension tap 3/8"-16 UNC?
This OSG extension tap has a 3/8"-16 UNC thread, H3 / 2B-3B tolerance, 4 flutes, plug chamfer, and is made from black oxide high-speed steel. The MPN is 1290801. It is designed for threading through holes and blind holes in ferrous materials up to 24 HRC.
Where to buy OSG extension taps worldwide?
3G Electric supplies OSG extension taps worldwide, handling full logistics and customs clearance. As a global industrial solutions provider, we source genuine OSG cutting tools like the 3/8"-16 UNC tap (MPN 1290801) and deliver to any international destination. Contact us for pricing and lead time.
How to select the correct OSG extension tap for a job?
Select an OSG extension tap based on thread size (e.g., 3/8"-16 UNC), material hardness, and hole depth. For blind holes, use a plug chamfer; for through holes, a bottoming chamfer. Match the H limit (e.g., H3) to your required thread class (2B or 3B). Always verify shank length clears the workpiece.
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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.
