Product features: 1 adopt imported high quality diamond powder, sintered metal powders made. 2 the holes neater and smoother, without broken edges and no tremor. 3 the cutting resistance, increase the speed of opening, after the slot is easy to decorate, and chip easily. Specification: 4MM-100MM specifications (straight shank, taper shank, screw shank) specification can also be non-standard products according to customer requirements. Glass drills with parallel Shanks primarily for drilling glass, can also be used for drilling of hard brittle materials such as stone, wear. complete specifications.