offers a set of diamond tile drill bits, consisting of 6 tile drill bits, including a 6mm yellow carbide drill bit (pre-drilled) and 5mm, 1*6mm, 1*8mm tile drill bit, 1*10mm and 1*12mm. NOTE: The yellow drill bit (pre-drilled) can only be used as an auxiliary tool for pre-drilling and should not be used for a long time, otherwise it will be easily damaged. In order to drill efficiently and beautifully, it is necessary to replace the blue drill bit after using the yellow drill bit to extend the life of the drill bits and improve efficiency. HOW TO USE: The procedure consists of first installing the yellow drill bit on the hand drill, tilting it at a 45-degree angle and rotating it quickly on the material surface. Then replace it with a blue diamond drill bit of the appropriate size and drill through the material without any problems. It is recommended to add water when drilling to cool the drill bits and extend their service life. These drill bits are suitable for materials such as