This Cressi Regulator is comprised of the MC5 Diaphragm first stage and the Ellipse Black second stage which has a black elastomer cover. This regulator is lightweight with fantastic performance whilst easy to maintain. The MC5 first stage has a sheathed sliding cylinder in the piston which has been made of a self lubricating polymer to reduce internal friction and eliminates any oxidisation that could effect the regulator performance over time. The MC5 has a special assistance chamber to trigger a Venturi effect between the intermediate pressure outlets and central diffuser, furthermore the balanced diaphragm not only maintains performance of the regulator if the tank pressure varies or depth increases but even increases performance in the critical and final stage of the dive. Other features include a filter to trap impurities from the incoming air and low and high pressure outlets are pre orientated for ideal hose placement.