These high-performance external pumps are ideal anywhere that a submersible pump cannot be used. As they are not self-priming, these pumps should be placed at a level lower than the bottom of the water tank concerned. This is the most effective way of preventing the pumps from running dry. & since they can be powered either from a car battery or via a mains adaptor, you have complete flexibility regarding setup location & power source. Work cycle of max. 30 min. No continuous operation possible.