HSS and Titanium Coating - High speed steel makes it more durable than others, titanium coating makes it easy to cut steel plate, aluminum sheet, copper, plastic, metal wood and many other types of sheet metal with ease. It can automatically deburr holes while drilling to keep the drill bit clean. Split point increases speed. home repairs and light work such as drilling holes in plastic, aluminum, copper and many other types of sheet metal. Package Contents: 1 HSS step drill 6-60 mm (12 steps: 6mm, 10mm, 15mm, 20mm, 25mm, 30mm, 35mm, 40mm, 45mm, 50mm, 55mm, 60mm) Meichoon step drill bits are made of high speed steel with titanium coating , which allows for a long service life.Features:1. High speed steel for longer life.2. Dual cutting blades design provides faster and smoother cutting.3. Advanced double spiral flute design outperforms straight flute design and extends bit life. The split tip increases speed, and it also includes laser-etched measurements to increase footstep visibility.4. Sharpness makes it easy to cut through most sheet metal, plastic and other materials.Specifications:Material: High Speed Steel.Step Drill Bit Sizes:12 Steps (6mm, 10mm, 15mm, 20mm, 25mm, 30 mm, 35mm, 40mm, 45mm, 50mm, 55mm, 60mm).Contents: 1 x 6-60mm drill bit. Note: The data are all manual measurement, please allow 1-3cm error, due to the light and display difference, there will be some color difference, depending on the physical object received. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.