The series are self-priming centrifugal pumps suitable for suction from deep wells, self-priming si achieved using and ejector, housed in the jet body, which can be installed directly on the pump body or more oftenlowered in a well and connected to the pump body by two pipes, the total delivery produced by the closed centrifugal impeller is sent only to the delivery opening.

The remaining water is recirculated through the ejector, whichis connected to the suction chamber where it generates the necessary vacuum to draw up water from the point where the jet body is immersed.

The water from the jet body opening mixes in the diffuser with recirculating from the pump, thus increasing its pressure at the expense of the reciculating water and is drawn into the pump through the suction pipe.