Self priming and ideal for continuous use sturdy polyamide casing the rotor is made of chemical resistant nitrile rubber which means you can use it not just for water but also for alkaline solutions diesel oil etc dirty water can be pumped without damaging the pump even with small stones once the pump is filled it is self priming even without a non return valve in the suction hose it will transport the water in both directions depending on the direction of the drill please use a 43