FIRST STAGE MK11 The MK11 model is a balanced membrane first stage, similar to the MK17 but without the sealed balance chamber. It is the ideal choice for sport divers who want to take advantage of the advantages of a membrane first stage in temperate waters. Membrane technology. The first membrane stages are isolated from the external environment, to prevent the ingress of water into the internal mechanism. Considering that the regulators generate temperatures down to -30 ° C following the exceptional speed of the gas flow and the pressure drop that occurs, it is essential that the moving metal parts do not come into contact with the icy water. For this reason, the first membrane stages are preferred by divers who dive in cold waters or work in polluted or rich in suspension waters. The SCUBAPRO membrane models are equipped with a particular balancing technology and take advantage of numerous patented innovations that allow them to guarantee a voluminous second stage air flow and an immediate response, which translate into extraordinary performance. Membrane balancing technology ensures constant performance regardless of cylinder pressure and depth and optimizes second stage performance by reducing respiratory effort. Two opposite high pressure outlets: the positioning of the high and low pressure hoses is crucial for the comfort of the dive. The presence of two opposite high pressure outlets allows to position the first stage in the preferred way (with the turret up or down). This allows the diver to position the instruments to the right or left and increases the freedom of movement of the head and neck. Multiple low pressure outlets: to ensure maximum freedom in the arrangement of the low pressure hoses, the MK11 model has four low pressure outlets in a fixed position, two of which are HP type. DIN / INT first stage configurations: to ensure worldwide compatibility, all SCUBAPRO first stages are available in the INT 200 bar version and in the DIN 300 bar versions. Intermediate pressure adjustable from the outside: allows SCUBAPRO authorized technicians to carry out precision calibrations or to repeat adjustments following maintenance operations without the need to dismantle the first stage. C300 C300 is a light second stage with anti-scratch cap, equipped with all the adjustment possibilities of the high-end regulators but positioned as a medium-level system. Optimal Flow Design (OFD) valve that ensures reliable and high air flow and improves respiratory work compared to a classic downstream valve. VIVA coaxial adjustment to control the Venturi effect and prevent self-delivery. Inspiratory effort adjustable in immersion. Redesigned mouthpiece conduit to facilitate exhalation.