Descriptions: These triangle glass drills are made of #45 steel shank, and high quality carbide reinforced head, strong toughness and wear resistance. Suitable for drilling in ceramics, glass, granite, ceramic tile and brick wall, etc. Features: Made of #45 steel shank, and high quality carbide reinforced head that prevents bit cracking and provides a longer life. Surface plating titanium treatment, which is well protected against rust. Strong toughness and wear resistance, applicable to ordinary hand electric drill or bench drill. Suitable for drilling in ceramics, glass, ceramic tile and brick wall, etc. It has 6 sizes(4mm, 5mm, 6mm, 8mm, 10mm, 12mm) in one set, which meet your different needs perfectly. Specifications: Material: 45# steel, Carbide Alloy Size: 4/5/6/8/10/12mm Surface treatment: titanium plating Weight:100g Packing Included: 6 x Glass Drill Bit