8Pcs/set 4 Blades Flute End Mill Cutter HSS Straight Shank CNC Milling Cutter Drill Bit Tools Diameter 2-12mm 5pcs set 2 3 4 5 6mm 2 flute or 3 flute or 4 flute milling cutter hss end mill cnc engraving bit straight shank drill bit tools