OSG Extension Tap: 1/4"-28 UNF, H3 / 2B-3B, 2 Flute, Plug Chamfer
The OSG Extension Tap (1/4"-28 UNF, MPN 1295101) is a spiral-point extension tap with a plug chamfer, made from black oxide high-speed steel. It features 2 flutes and is rated H3 / 2B-3B for thread class compatibility.
SKU 3G-OTH-313569
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Product Description
The OSG Extension Tap (1/4"-28 UNF, MPN 1295101) is a spiral-point extension tap with a plug chamfer, made from black oxide high-speed steel. It features 2 flutes and is rated H3 / 2B-3B for thread class compatibility.
Frequently Asked Questions
What is the OSG Extension Tap 1/4"-28 UNF used for?
The OSG Extension Tap is used for threading blind or deep holes in metalworking, particularly where standard taps cannot reach. Its extended length allows access to recessed areas in automotive, aerospace, and general manufacturing applications. The 1/4"-28 UNF size creates fine threads in steel, aluminum, and other materials.
What are the specifications of the OSG Extension Tap MPN 1295101?
This OSG Extension Tap has a 1/4"-28 UNF thread size, H3 / 2B-3B tolerance, 2-flute design, plug chamfer, and black oxide high-speed steel construction. The H3 tolerance ensures precise thread fit for class 2B or 3B holes. It is designed for spiral-point geometry to push chips forward in through-hole applications.
Where to buy OSG Extension Tap 1/4"-28 UNF worldwide?
3G Electric supplies the OSG Extension Tap 1/4"-28 UNF (MPN 1295101) worldwide. As a global industrial distributor, we handle full logistics, customs clearance, and delivery to your facility. Contact us for availability and lead time. We source genuine OSG tooling for manufacturing and maintenance operations.
How to select the correct OSG extension tap for a job?
Select the OSG extension tap based on thread size (e.g., 1/4"-28 UNF), hole depth, and material. The H3 / 2B-3B tolerance suits precision threading. Use a plug chamfer for blind holes and a 2-flute spiral-point design for through holes. Match the tap to your workpiece hardness and machine type for optimal thread quality.
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3G Electric supplies OSG spiral-point extension taps. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.















