Atoplee 6pcs CNC PCB Router Bit Drill Corn Milling Cutter Shank 1/8'' [1.0/1.5/3.175mm, 2 of Each] Material: tungsten steel alloy Shank diameter: 3.175mm(1/8") Total length: 38mm Blade diameter: 001: 1.0mm, 002: 1.5mm, 003: 3.175mm ;Blade length: 001: 7.2mm, 002: 9.5mm, 003: 14mm Package Included: 6pcs Corn milling cutter