High Quality MaterialMade of hard alloy, this glass drill bit has very good abrasion resistance and extreme hardness for long service life. The titanium coated surface is anti-oxidant and does not fade.7 sizes Glass drill bit with 7 different sizes: 3mm, 4mm, 5mm, 6mm, 8mm, 10mm, 12mm, the all in 1/4" hex shank, perfect for various tasks, this drill bit is size markedPrecise and Smooth HoleExcellent for drilling clean and precise holes in glass and The edge of the drill bit is fine, and the hole is smooth and full, without leaving any burrsSturdy & Durable Hex shank glass drilling tools are sharp and change quickly. using water lubrication will greatly extend the life of the bitWide Application Indispensable for DIY and home improvement enthusiasts in glass tile ceramic mirrors and other surfaces hard and brittle work