Accessories screwing, drilling -Drill Bits Wood Alloy Drill Bits Ceramic Countersink bottom Highlights brand generic Drill Bits Wood Alloy Drill Bits Ceramic Countersink bottom Description: Please add water for coolant and drill slowly Start drilling at 45 degrees from the surface and align at 90 degrees as holes Never use drill bits when the machine is in hammer action Holes require no extra work as the cut is clean Suitable for various stones, ceramics, vetrified tiles , glass, marble, etc. Specification: Material: Diamond Total Length: apprxo. 6.5cm / 2.56inch Upper rod diameter: 8mm / 0.31inch; Tapping diameter: 22mm / 0.87inch Color: Red Package includes: 2 pieces of glass drill bit Note: Please allow 1-3mm error due to manual measurement, make sure you do not mind before you are bidding Colors may be different for the different displays, please understand