1.Type:HSS,TCT,Bi-metal,wood,glass,marble,plane,grit,spherical 2.Suitable for:steel,wood,glass,marble,hollow 3. ... Pack:bulk,set 1, blade and blade all use H.S.S HSS ... hole on cold hard materials, cutting into should inspect the blade temperature to add.Note cooling fluidDiameter:15-150mmlength:70mm HSS Hole Saw ...