ITEM NAME:Ti (13 Steps 5 7 10 12 15 17 20 22 25 27 30 32 35MM) High Step Drill Bit #gib Product Description Description: Features: 5-35MM(13steps:5,7,10,12,15,17,20,22,25,27,30,32,35MM) Material: high speed steel 6542/M2 (suitable for use on the workpiece, the hardness of 28 degrees such as stainless steel, aluminum, carbon steel, plate, insulation board, PVC board, wood, sheet thickness below 3MM) Surface treatment: TI Included: 1 X Step Drill Bit.Included:1 X Step Drill Bit. Material: high speed steel 6542/M2 (suitable for use on the workpiece, the hardness of 28 degrees such as. stainless steel, aluminum, carbon steel, plate, insulation board, PVC board, wood, sheet thickness below. ).