The Emperor Aquatics Smart Lite UV Sterilizers are designed for aquarium owners and pond keepers who appreciate quality and performance but are restricted with space. The Emperor Aquatics Smart UV Lite features a space saving 2" diameter body constructed of UV resistant plastic. All models are watertight, corrosion resistant, and designed for safe operation in outdoor environments. Connections: 2" slip inlet/ 2" slip outlet. A pump is required. The required flow rates:-Algae: 554 gph maximum, 332 gph minimum; -Protozoa: 184 gph maximum, 110 gph minimum. Dimensions: 29.75" X 2.5".