*Made of high speed steel material, stable and durable to use. *Titanium plating treatment. *Two Flute Design For Faster, Smoother Cutting. *The step drill bits Set replaces 29 individual drill bits. *High strength, hardness and easy to use. *Suitable for Drilling in Wood, Plastics, Steel, Aluminium and other Non Ferrous Metals. Specifications: *Material: High Speed Steel *Color: Gold *Surface Treatment: Titanium Plating *Strp Drill Bits: 4-12mm / 4-20mm / 4-32mm *Saw Drill Bits: 3mm / 6mm / 8mm *Include: 3pcs Strp Drill Bits & 3pcs Saw Drill Bits Package Contents: 3*Step drill (4-12/20/32mm) 3*Saw drill (3/6/8mm) 1*Storage Box or 3*Step drill (4-12/20/32mm) 3*Saw drill (3/6/8mm) 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.