Milwaukee #4 Step Drill Bit delivers jam- performance with a dual-flute design that provides up to 2X faster hole times, up to 4X longer life, and up to 50% more holes per battery charge d to the competition. This step drill bit is for drilling both large and small-diameter holes in steel and plastic, optimized specifically for high-speed cordless drills. The Rapid Strike™ tip enables fast, accurate starts while generating less heat to extend the life of the bit tip. Its black oxide coating enhances durability, hole quality, and overall bit life. For added convenience and precision, laser-engraved reference marks are visible during drilling. The 3-flat Secure-Grip™ shank ensures a solid connection with the drill chuck. This #4 step drill bit features 12 hole sizes in 1/16" increments, ranging from 3/16" to 7/8", and jam- performance at high speeds with most professional 18 Volt cordless drills using lithium-ion battery technology. Model Number: 48-89-9204