Size 4. Drilling range 24.0-40.0 mm. This robust tool allows sheets to be centered, pre-drilled, and continuously drilled in one operation. The deeply ground flutes ensure absolute smoothness and high cutting performance. The taper facilitates retraction when drilling through sheets. This sheet metal step drill is designed for high demands in industry and craftsmanship. The titanium nitride wear protection coating increases the surface hardness to approximately 2,300 HV and the heat resistance to about 600 °C.