The Aquapro UV sleeve is a protective tube made of high-purity quartz glass that encases the UV lamp within the stainless steel or plastic reactor chamber. Its design is crucial because it creates an insulating, watertight barrier, protecting the electrical components of the lamp from direct contact with the water. Critically, the quartz material allows maximum transmission of the germicidal UV-C light into the water. Maintaining a clean sleeve, free from scale or mineral buildup, is paramount for the system's effectiveness, as even a thin layer of scale can block the UV light, severely reducing the disinfection capacity.