Diamond Hole Saw 1" a core bit for tile, porcelain, hard stone, granite, marble, brick and concrete counter tops.  Fast Cutting. 3-3/8" long, 2-1/4" cutting depth, 5/16" shank works great with all hand drills. If you need to drill through tile, marble or any lapidary and have a drill, this is the product. Comes with cooling holes. Use water with spray bottle to keep hole saws cool while extending drilling life. Can be used wet or dry.