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. For aquarium or pond use-For aquariums up to 75 gallons. The 75 gallons rating assumes the unit is being used as a clarifier (algae) and sterilizer.-For ponds up to 2,000 gallons18 watt T5 UV lampIn lineConnections: 2" slip inlet/ 2" slip outletA pump is a required. The required flow rates:-Algae: 365 gph maximum, 219 gph minimum-Protozoa: 121 gph maximum, 73 gph minimumDimensions: 21.75" X 2.5"Accessories:2" Mounting Bracket for Emperor Aquatics Smart Lite UV Sterilizers1 inch Bushing-Hose Barb Kit for 2 inch inlet/outlet (pair)3/4 inch Bushing-Hose Barb Kit for 2 inch inlet/outlet (pair)