MILWAUKEE #4 STEP DRILL BIT - 3/16" TO 7/8", BLACK OXIDEThe Milwaukee #4 step drill bit produces 12 clean hole sizes from 3/16" to 7/8" in 1/16" increments, covering the widest single-bit range on the jobsite for sheet steel, aluminum, copper, 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.
- 12 steps from 3/16" to 7/8" in 1/16" 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.
Selection Tip: The #4 has the broadest range in the family -- one bit that covers everything from small pilot holes through 1/2" and 3/4" conduit knockouts up to 7/8" cable-gland and panel-mount fittings. The trade-off vs the #3 is a slightly bigger, heavier bit; trade-on is you stop swapping bits mid-job.