Durable split bit for fast, precise material penetration. The patented split step design optimizes chip loading for a fast, smooth cut and more holes per charge. The progressive cutting edges provide balanced aggression to maximize torque efficiency and minimize jamming. The double-flute design provides superior chip evacuation, cutting speeds, and tool life. Three-flat shank fits all 1/2-inch drill chucks. Laser-etched markings for quick and easy product and size identification. Replaced 34401 Also available for sale in a carton, qty. 25 (Cat. No. GSB01-B UPC No. 783310082057) Features Type: Multi-Hole Step Cutter Application: Cuts mild steel, aluminum, brass, copper, wood, fiberglass, plastics, and laminates Number of Drilling Steps: 13 Minimum Drilling Diameter: 1/8 in. (3.2 mm) Maximum Drilling Diameter: 1/2 in. (12.7 mm) Maximum Sheet Metal Thickness: 10 gauge (3.5 mm)