Milwaukee Step Drill Bits with JAM-FREE Performance feature a dual-flute design delivering up to 2 times faster hole times, up to 4 times longer life and up to 50% more holes per battery charge than competitors. Ideal for drilling small and large-diameter holes in steel and plastic, these bits are optimized for Cordless Drills in High Speed. The Rapid Strike tip allows for a fast and accurate start that generates less heat, resulting in longer bit tip life. Black-oxide coating also enhances durability, hole quality and bit life. For user convenience and accuracy, each bit has laser-engraved reference marks you can see while drilling. The 3-flat Secure-Grip shank ensures a solid connection with the drill chuck. The Step Drill Bit 3-Piece Set includes bits #1 (48-89-9201), #2 (48-89-9202) and #4 (48-89-9204). Jam-Free Performance in high speed with most professional 18-Volt cordless drills with lithium-ion battery technology.