JBL - PROTEMP e300 Flow Heater In-line heater integrated into the tubing of the external aquarium filter, eliminating the need for a heater INSIDE an aquarium Easy installation: cut through the hose from the external filter that returns the water to the aquarium, insert the external heater in between, plug in and set the desired water temperature The integration in the filter circuit ensures a very even distribution of the water temperature with an accuracy of +/- 0.5 °C and a change interval of 1.0 °C in the aquarium LED display of current and desired temperature. Interchangeable, screwed on (3/4'') hose connections for 12/16, 16/22 and 19/25 mm incl. hose protection. Total length 30.5 cm Package contents: 1 in-line heater 300 W for aquariums from 90-300 l (80-120 cm) with hose connections for 12/16, 16/22 and 19/25 mm and cleaning brush