The Milwaukee #12 step drill bit produces 5 large hole sizes from 7/8" to 1-3/8" in 1/8" increments, the upper-end range for 1/2" through 1" conduit knockouts, panel-mount switches, large cable glands, and big grommet cutouts in steel, aluminum, and plastic. The dual-flute geometry chips fast, the Rapid Strike tip self-starts without a punch mark and runs cooler than a single-point bit, and the 3-flat Secure-Grip shank locks into a standard drill chuck without spinning under load.

• 5 steps from 7/8" to 1-3/8" in 1/8" increments
• Drills sheet steel, aluminum, copper, brass, and plastic up to roughly 1/8" thick
• Dual-flute design clears chips fast and cuts cooler than single-flute step bits
• Rapid Strike tip self-starts and runs cooler, prolonging cutting-edge life
• Laser-engraved size marks on each step for quick identification
• Black oxide coating reduces friction and resists corrosion
• 3-flat Secure-Grip shank locks into standard 3-jaw and quick-change chucks

Application Tip: Step bits are the right tool for thin material -- up to about 1/8" thick. Use the high speed setting on a cordless drill, apply firm steady pressure, and stop drilling the moment the next step's shoulder reaches the workpiece. For sheet metal, a few drops of cutting oil cool the tip and produce a cleaner hole edge. Use a 1/2"-chuck drill or impact driver -- 3/8" chucks may struggle to hold this larger shank under heavy cutting torque.

Selection Tip: The #12 is the large-conduit and panel-mount bit -- 7/8" and 1-1/8" for 1/2" and 3/4" conduit knockouts, 1-3/8" for 1" conduit fittings, plus intermediate sizes for big cable glands and panel-mount circuit breakers, switches, and pilot lights.