The peripheral edge of the impeller contains numerous radial blades, designed to yield energ to the fluid being pump. The shape of the blades rapidly transfers radial recirculation motion to the fluid on entry to the pump, between the impeller blades and the double channel, machined on each side of the pump body. Since each of the numerous blades help transfer energy, the fluid pressure increases progressively as it passes from the suction opening to the delivery opening, ensuring an even, non pulsing flow and high pressure with particularly steep curves. The relative simple construction technology embodied in the series nevertheless requires particularly accurate mechanical machining during manufacturing to prevent a drop in performance.