The most technically advanced aquarium heater available delivering wide temperature control with LED warning alert system. Features: Fits as intake tube to all RENA SmartFilters and RENA Filstar xP1 through xP4 Canister Filters or by itself as a conventional heater Patented interactive display LED lighting with "abnormal temperature" alert flashes fast when water is +/- 5°F from set Five models: 50, 100, 150, 200, 300 watt Made with high quality, durable and unbreakable plastic meeting UL standards. Safe to touch even when heating Energy-efficient tubular design heating both internal and external surfaces of the heater Super accurate set up temperature knob with wide temperature range (69°F–93°F) Benefits: Allows for a less cluttered tank and more even heating in one integrated system! Communicates directly with hobbyists to protect fish even under formerly uncontrollable dangerous circumstances A heater to fit all sizes of aquariums Increased consumer comfort, confidence and safety; less returns Provides even heat distribution preventing unwanted temperature variations within the aquarium Allows hobbyists to have extremely accurate temperatures to mimic all types of aquarium environments Info from marine Depot