👍【High Quality ZnSe Crystal】China PVD ZnSe material. High temperature resistance, no adsorption of impurities, small leakage loss. Excellent optical properties. Can resist up to 100W CO2 laser. 👍【Lasting Durability】Our FONLAND focus lens with Superb Double-sided Solid Coating. Wiping Resistance. Long Working Life. 👍【High Transmittance】High Quality Material and Exquisite Double-sided Coating to reduce the loss of laser. Laser Transmittance Up To 99.5%. Higher Work Efficiency. 👍 【Wide Application】DIY replacement parts for CO2 laser engraving, cutting and marking machines and CO2 laser heads. Our FONLAND focusing lens supports CO2 laser engraving and cutting machines below 100W. 👍【Support Customize】This product is suitable for laser wavelength λ=10.6μm. If you need a special focal length we can customize it for you. Please feel free to contact us if you have any problems or customized requirements., Manufacturer: FONLAND