... !!! a set of 20 new diamond tiped hole saws (Core Bits)with case.You can cut the following size holes 4mm, 5mm ... , 32mm, 35mm, 38mm, 40mm, 45mm ,50mm 55mm, 60mm. ENGINEERED TO CUT HOLES IN GLASS, TILES, SLATE, MARBLE ,GRANITE with ease!!! Best ... AT A LOW SPEED WITH A SPRAY BOTTLE FOR WATER. Diamond Tipped tile stone glass Hole Saw