The novel PTC aquarium heaters made of titanium tubing are particularly energy-efficient, as their output depends on the heat extraction. If a lot of heat is extracted from the heater, it readjusts its temperature independently and increases its output. As soon as it reaches its maximum temperature, the power decreases again and hardly any current flows. Thanks to this self-regulating property, PTC heaters cannot overheat, which makes them particularly safe. The SCHEGO heating rod is attached to the aquarium pane with the supplied suction holders. The heaters are made of high-quality titanium tube, therefore they are unbreakable and sea water-proof. All heating elements are grounded and guarantee a high safety standard. The heater is unregulated it is recommended to use the SCHEGO Controller TR 1000.technical Data SCHEGO PTC Titanium Heater:PTC 100 Wfor aquariums up to: 100 llength: 150 mmdiameter: 12 mmcable length: 150 cmprotective system: IP68PTC 200 Wfor aquariums from 100 up to: 2