These hole cutters are good for drilling through glass and many other similar materials like ceramic, porcelain......
Although they can go through other materials like granite, marble, concrete, brick... but they are NOT suitable for cutting such materials.
For better performance and longer life it is adviced to use water or coolant liquid.
Available sizes from 6 to 120mm, please visit our shop.
The water supply adaptor is not included, photo for illustration, can buy it separately, please visit our shop or go to the link below:
http://www.ebay.co.uk/itm/12211501-Glass-Ceramic-Diamond-Core-Hole-Drill-Bit-Water-Supply-Attachment-/281525520644?