It’s an hydro-pneumatic system of the machine passive weights support, it is constituted by a conventional hydraulic ram, connected directly to a series of hydro-pneumatic accumulators which guarantee a direct hydraulic force to the hydraulic ram. A multi-function solenoid valve unit, electronically managed, controls the correct functionality and the pre-charge pressure of the system. Through this system, the hydraulic power used for the handling of the load is real. In the exclusive movement of the primary arm, the saved fuel can reach up to 50%, in work combined movements, the economy is around 20%.