Product details:

Drill America Qualtech DWC series annular cutters are designed for fast, efficient hole making. Universal cutters cut only that material necessary to produce a quality hole. Works with hougen magnetic drill and similar machines. High-speed steel tools are good for most general purpose applications, offering a combination of hardness and toughness for wear resistance. Weldon shanks feature a round shank with one of more flats machined into the side for easy indexing and alignment. When run in a counterclockwise direction (right-hand cut) spiral fluted tools evacuate chips up and out of the cut to reduce clogging. Fits most magnetic drill presses.