RUKO Step drill set dm 4-12/4-20/4-30 mm HSS spiral-grooved 3-part metal box

The deep and spiral-shaped chip groove ensures absolutely smooth operation and a high cutting capacity. In particular, non-breaking chips are cleanly transported away, just like they are with a twist drill. This prevents the formation of built-up edges and cold fusing on the cutter. The cone makes the drill easier to retract once sheet metal has been drilled through.
– In metal box