CO2 LASER MARKING MACHINE ( 30W / 60W / 100W / 150W ) Water / Air Cooling. Laser Wavelength 10.64μm / 9.3μm. CO2 laser marking machine utilizes CO2 gas as working medium. It generates laser light with a wavelength of 10.64μm/9.3μm through high-voltage discharge.After scanning and focusing with galvanometer, it marks the workpiece surface. The machine mainly engraving on various non-metallic materials.