This replaceable blade system provides maximum productivity by eliminating downtime and the cost to resharpen. Each bit comes standard with a second replacement blade allowing the bit to cut like new again. Replacement blades are made with hardened steel for long life. Size is engraved on each blade. SwitchBlade self-feed bits are designed for drilling holes in all types of wood for pipe, vents, gas lines, and bulk wire routing. The product is manufactured in China.