Bi-metal hole saw with HSS-Co teeth in variable tooth pitch, welded onto a cylindrical tool steel body, the saw core can be easily removed in conjunction with the PUMPSHANK®, for cutting round shapes in steel and non-ferrous metals such as copper, bronze, brass, and aluminum. The high-quality cobalt alloy and special custom grind achieve better cutting performance and longer service life. Cool the hole saw with cutting oil when cutting metals; for plastics, gypsum, and wood-based materials, we recommend the PAROLI 50 HM hole saw series 2166.