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 IRW10501918 Granite 7 piece drill bit set contains the following pieces:
4.0, 5.0, 6.0, 7.0, 8.0, 10.0 and 12.0mm