Carbide Coolant Drill Bits are used in drilling machines or CNC machining center which feed coolant directly to the cutting edge during operation, reducing temperatures and flushing chips out of the hole for faster work, longer lifetime.straight shank models are used in appropriate coolant-fed holders. Large holes at the point end improve coolant flow to the workpiece for decreased friction and better chip removal. Suitable for a variety of stainless steels, cast iron, and other ferrous and non-ferrous metals and alloys.