Product Description EASY TO USE The medium guide tips are suitable for wood, metal, etc. How to keep the drill on target:a- You can make your own guide out of plywood - plastic or even cardboard - just hold the drill in place until it leaves the first marks.b- You can start drilling at an angle with the edge of the drill forming a C-shaped groove and then guide the drill vertically.c- You can manually guide the drill with a damp sponge. Applicable industry: suitable for processing stone, tile, ceramic, glass and granite, etc. Package includes: 1 * Diamond Drill Bit Set Material: Iron, Diamond on the head Color: Silver Quantity: 15pcs TIPS: If the tool overheats, the electroplated diamond coating will wear out. Never let the drill dry How to use water to cool the tool: a- You can build a mini water dam around the hole using plumber's mortar. b- You can spray the tip with water. c- Or you can also use running water to cool the tip. Steps: Start drilling from the opposite corner, draw a