HRC45 HRC50 HRC55 HRC60 HRC65 4/2 flutes 12x150MM 12mm Tungsten Carbide End Mill R6 ball end End Mill Aluminum milling cutter r0 4x0 8x6x4x50l 20pcs deep neck groove carbide ball nose end mill 2 flutes hrc55 with coating cnc milling cutter