OSG 1/4"-28 UNF Spiral-Flute Extension Tap
The OSG Extension Tap (MPN 1298300) is a 1/4"-28 UNF spiral-flute extension tap, type H3 / 2B-3B, with a bottoming chamfer and 3 flutes, made from high-speed steel.
SKU 3G-OTH-310959
Local availability & support
- Delivery
- Worldwide DHL shipping from Singapore; 7–14 business days door-to-door for most destinations.
- Payment
- Invoicing in USD. Bank transfer (SWIFT) and corporate PO accepted.
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Product Description
The OSG Extension Tap (MPN 1298300) is a 1/4"-28 UNF spiral-flute extension tap, type H3 / 2B-3B, with a bottoming chamfer and 3 flutes, made from high-speed steel.
Frequently Asked Questions
What is the OSG Extension Tap 1/4"-28 UNF used for?
The OSG Extension Tap is used for threading blind holes in hard-to-reach locations, such as deep bores or recessed surfaces in automotive, aerospace, and general machining. Its bottoming chamfer and 3-flute design allow threading close to the bottom of a hole, while the extension provides clearance for obstructions.
What are the specifications of the OSG Extension Tap MPN 1298300?
This OSG tap has a 1/4"-28 UNF thread size, H3 / 2B-3B tolerance, 3 flutes, and a bottoming chamfer. It is made of high-speed steel (HSS) and is designed for threading blind holes. The manufacturer part number is 1298300, and it is classified as a spiral-flute extension tap.
Where to buy the OSG Extension Tap 1/4"-28 UNF worldwide?
You can source the OSG Extension Tap MPN 1298300 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 supply this tap to procurement teams and engineers globally.
How to select the correct OSG extension tap for a threading application?
Select an OSG extension tap based on thread size (e.g., 1/4"-28 UNF), chamfer type (bottoming for blind holes), flute count (3 for chip evacuation), and material compatibility (HSS for general steel). Ensure the tap's reach and shank length clear the workpiece obstruction. Consult OSG's technical data for optimal speeds and feeds.
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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.