Features: *100% brand new and high quality. *High quality materials . It is made of high quality YG8 alloy as raw material. The process of oxynitriding of the cutter head strengthen the drill hardness. *UNIQUE CROSS ANGLE DESIGN Small incision resistancefeature drilling stably, fast speed, not breaking the border. Opening neat, smooth, no broken edges, no tremor phenomenon, chip easily. *WIDE USAGE Professional glass and tile drill bits provide smooth and accurate drilling in ceramic tiles, marble, thin iron plate, mirrors and glass. Remember to add Water or coolant when drilling. *5 DIFFERENT SIZES Suitable for your different needs.It Can be installed in the general electric hand drill, bench drill. The machine drill clamp range is 10mm and above. Specifications: Material: Cemented Carbide Color: As picture show Size: 3*70mm, 4*70mm, 5*76mm, 6*77mm, 8*80mm (Approx.) Quantity: 5pcs Package Contents: 5*Universal Drilling Tool