Description:This bit for the hard brittle ceramic material，such as glass and so on.It can be used with the ordinary drilling hammer.It must be add coll-ant when it is being used.<br>Specifications:Drill 1: approx 6mm*77mmDrill 2: approx 8mm*82mmDrill 3: approx 10mm*85mm<br>Usage:When drilling the hole，your force should be slow，especially at the beginning of drilling and when it is drilling the glass through.Turn on the right when working speed 400-500.<br>Package included:3 X  Drill Bits