JET self-priming jet pumps consist of an enjector unit and a centrifugal pump connected in series.The ejector unit can be lowered in a 4" diameter pipe of well. These pumps are suitable to convery clean water or non-aggressive chemical fluids;they are extremely reliable and simple to use and are suitable for domestic applications,for automatic distribution of water from small to medium size surge tanks and for boosting systems.In order to grant a correct conter-pressure,it is always advisable to install a foot valve with a strainer on the suction nozzle.