High-quality steel base. Durable lamps with an inside protective coating that ensure constant UV output over the complete lifetime. OZONE-FREE: Special lamp glass filters out the 185 nm ozone-forming radiation. No irritating smell. Short-wave UV radiation with a peak at 253.7 nm (UVC) is perfect for disinfection purposes. Designed to be installed on your HVAC Duct to provide an antimicrobial and antibacterial defense. It helps to keep your air conditioner free of odors and the moldy smell. Safe to use: A sign on the bulb indicates that the bulb produces UVC wavelengths. 254 nm UV-C energy destroys the DNA of airborne contaminants (bacteria, viruses, mold spores, yeast, and protozoa)