Features: *Made from high quality HSS steel. *Heat treated and highly polished. *With the Nitrogen Coated to reduce friction and heat. *Perfect for home DIY and general building / engineering use. *Ideal for using to cut holes in a variety of materials including steel, brass, wood, plastic,copper, fibreglass and PVC etc. *3 sided shanks design in order to prevent slippage when in chuck. *Two flute design provides faster, smoother and cleaner cuts. *Each step is clearly labeled with the depth diameter in steps Specifications: *Material:HSS Steel *Color: Black *Finish: Nitrogen Coated *Length: 3-12mm Length: Approx.5.2cm/ 2.04" 4-12mm Length: Approx. 4cm/ 1.57" 4-20mm Length: Approx.4.7cm/1.85" The 3 Cutters Come in the Following Sizes: 4-12mm: 4, 6, 8, 10, 12mm 4-20mm: 4, 6, 8, 10, 12, 14, 16, 18, 20mm 3-12mm: 3, 4, 5, 6, 7, 8, 9, 10, 11, 12mm *Quantily:1/3/5PC Package Contents: 1/3/5PCS*Step Drill Bit Note: 1. The real color of the item may be slightly different from the pictures shown on website caused by many factors such as brightness of your monitor and light brightness. 2. Please allow slight manual measurement deviation for the data.