Bi-metal hole saw,M3/M42 bi-metal construction for heavy duty cutting ... 8"(35mm)and1-7/8"(47mm) Bi-metal hole saw,M3/M42 bi-metal construction for heavy duty cutting, ... and1-7/8"(47mm)Product name: Bi-metal hole saw*M3/M42 bi-metal construction for heavy duty cutting*cutting ... )*can be used in portable electric or pneumatic tools, vertical drill machines, lathe,boring/milling machines and other machine ...