BI-METAL HOLE SAW 1-3/8" Bi-Metal Hole Saws - All-Purpose, BearcatT, Variable Pitch- Saw Diameter:1 5/16" Bi-metal hole saws are constructed of hardened, heat & abrasion resisting high speed steel teeth. This gives them exceptional strength, durability and shatter resistance for user safety. They will cut any wood, metal or plastic in either a hand-held drill or a drill press. Cut through any wood,metal/plastic & can be used in a wide variety of applications from production.