Product features: 1: the use of imported high-quality diamond powder, metal powder sintering. 2: the opening of neat, smooth, no broken edge, not the thrill of the phenomenon. 3: small incision resistance, improve the opening speed, easy to decorate after slotting, chip easily. Specifications: 4MM-100MM complete specifications (straight handle, taper shank, screw shank) special specifications can be produced according to customer requirements of non-standard products. Straight shank bits of glass is mainly used for drilling in glass, can also be used for drilling in stone and other hard and brittle materials, sharp and durable. Specifications.