The Silverline bi-metal hole saw has variable pitch teeth to guarantee a clean cut. The industrial strength HSS M3 cutters are made from a flexible high carbon steel. The sizes include 20mm, 25mm, 32mm, 38mm, 51mm, 64mm, 70mm, 127mm and 152mm. They will cut wood, PVC, cast iron, alloyed aluminium, non-alloyed aluminium, stainless steel, copper, structural steel, acrylic and bronze.
NOTE - When drilling metal always use a lubricant on the cutting area to greatly extend the life of the hole saw teeth.