The Ci Series Weather-Ometers are the most widely used rotating rack water-cooled xenon-arc weathering testing instruments in the world. Their large capacity and full-functional performance make these instruments the best choice for a wide variety of accelerated weathering test methods. They offer superior irradiance and temperature uniformity within the test chamber, as well as a wide performance envelope for all weathering testing parameters. They are commonly referenced in OEM weathering test standards and specifications. The intuitive user interface makes operation and programming very simple. Several revolutionary options and accessories are available to allow researchers to get the most out of their weathering testing programs.