The Irwin Unibit No. 9 High-Speed Steel Knock-Out Drill Bit features the whole sizes for the most popular electrical box knock-outs. The single-flute design lets you drill true, round holes every time and gives you ultimate control over the drill progression. The laser-marked sizes allow fast, sure whole identification.
- Requires minimum chuck size of 1/4 in.
- Speed point tip for fast starting
- High-speed steel
- Hex-shaped shank provides an easy gripping surface for the drill