Package includes: A drill group (with 7 specifications drill bits) Suitable for glass, ceramics, metal marble, granite, etc. Just installed in ordinary Electric drill can be used, first the drilling angle of 45 degrees, after vertical Drilling, the force should be soft. Features: Material: metal Color: silver Length: 5cm Diameter: 10/25/40/55/70/85/100 mm Application: Glass, ceramic tiles, marble, granite and others fragile hard materials Features: 1.Unique opening design, strong drilling, easy to operate 2. Open to the hole, smooth, without broken edge, will not produce the tremor phenomenon 3.Easy incision resistance, Improve the opening speed, Easy to trim after the slot How to use 1.Installed in an ordinary electric drill 2.First 45 degree angle drill position, then vertical drilling 3.Force should be light slow, especially at the beginning of drilling and drilling to slow 4. When opening a hole, water must be added during the operation Notice To keep the water drill, remember to drill dry