The purpose of overcentre valves is to mantain a set pressure opposite a load, keeping it form free- falling. Now, thanks to the new advancements in overcentre valves technology, controlling a a load smoothly has become much more easier especially when pumps and actuators become more advanced and, at the same time, directional control valves become more comlplicated. In selecting this kind of element, one fundamental parameter to take to take in to consideration is the release characteristic that is based on the direct coherence between the pressure and the flow via the valve. Often unwanted oscillation in applications like crane booms or lifting platforms are caused by over dimensioned flow cross sections or insufficent dampening of these valve types and, consequentially, all the latest developments in this peculiar domain aim at creating a valve that can unify both sufficent dampening and good responsiveness. This special technical discovery could represent a real help for the needs of customers manufacturing mobile machines. so now many suppliers of valves are trying to do their best to create special products for hydraulic systems in the mobile and fixed sectors: all these items have been projected in order to meet the specific requirements of every type of customer.