The Irwin Granite drill bit range have been designed for for impact / percussion drilling in very hard materials such as granite, concrete and natural stone.

They can drill 40% more holes than conventional masonry drill bits due to an extra hard, thicker and more robust carbide tip. The rounded cutting edges means higher durability resulting in 50% more accurately sized holes per drill bit.

The Irwin IRW10501914 Granite drill bit has the following dimensions:
Drillbit diameter: 12.0mm
Total length: 160mm
Working Length: 130mm