OSG #4-40 UNC Spiral-Flute Extension Tap

The OSG #4-40 UNC extension tap is used for threading blind holes in hard-to-reach areas. Its 2-flute, bottoming chamfer design allows threading close to the bottom of a hole, while the extended length provides access in deep or obstructed applications. It is suitable for use in steel and other materials requiring precise internal threads.

The OSG extension tap MPN 1296100 is a #4-40 UNC tap with a H2 / 2B-3B thread class. It has 2 flutes, a bottoming chamfer, and is made from high-speed steel. The spiral-flute design aids chip evacuation. This tap is designed for threading blind holes and is part of OSG's spiral-flute extension tap product type.

You can source OSG extension taps, including the #4-40 UNC model MPN 1296100, through 3G Electric. As a global industrial equipment distributor since 1990, 3G Electric handles full logistics, customs clearance, and delivery to worldwide destinations. Contact 3G Electric for availability and lead time on this OSG tap.

To select the correct OSG extension tap, match the thread size (e.g., #4-40 UNC) and thread class (e.g., H2 / 2B-3B) to your hole requirements. Choose a bottoming chamfer for blind holes and a spiral-flute design for chip evacuation. Ensure the tap length provides sufficient reach. OSG taps are precision-ground from high-speed steel for durability.