High Speed Steel 2 Flute Stepped Cone Drills are designed for drilling and enlarging perfectly round holes from 1/8" to 1-1/2" diameter in thin materials up to 1/8" thick. No pilot hole is required. Self-starting split point prevents walking. Each hole is automatically deburred by the cutting edge of the next larger size. Ideal for drilling sheet metal, non-ferrous metals, plastics, PVC, laminates, or wood. They are also known as Step Drill Bits or Step Drills.