Combining the original D-Series regulators’ iconic design with the latest advances in breathing performance technology, SCUBAPRO engineers have created a 21st-century regulator in terms of quality, reliability, performance, and style.

The new D420 features a brand-new balanced valve inside a housing supported by a full metal structure. Called the Progressive Flow Control Valve, it can deliver excellent airflow for the best breathing performance, with a natural smoothness comparable to what you might experience breathing on the surface. The uniquely shaped fiberglass-reinforced nylon casing is ultra-durable and allows the LP hose to be connected on either the right or left side for maximum rigging flexibility. A new dive/pre-dive system includes a switch on the top of the casing with a thumb tab for adjusting the direction of airflow right out of the valve. The highly efficient purge button is a technical jewel based on a new concept that gives the D420 its unique face — teamed with the MK25 EVO balanced piston first stage, a regulator system purpose-designed for avid and professional divers.

SCUBAPRO has been a Leader in the Evolution of piston controlled first stages since it was started in 1963; the MK25 EVO carries on this heritage with an array of patented features ensuring unfailing performance. The MK25EVO is a balanced piston first stage and is one of the best in its field. It is a superior regulator because of its ultra-stable intermediate pressure (IP), resulting in extraordinarily punctual and constantly high air delivery.

Air balanced, flow-thru-piston first stages with air balanced pistons deliver significantly more air to the second stage than any other first stage. At the same time, their performance is totally unaffected by the changing tank pressure. A balanced piston allows the use of lighter and more sensitive components, resulting in ultra-fast breathing response, instant delivery of air on demand, and extra-high airflow, especially in low tank pressure ranges. This benefits a tired diver giving them a smoother breathing regulator during all stages of the dive, from the descent to the ascent or deco stop. Balanced piston first stages are the first choice of demanding sport divers and professionals. A balanced piston performs equally in warm and cold-water environments.

Cold Water Diving conditions can be different, including extreme cold water and outside temperatures, posing the possibility of a regulator “freezing.” Therefore, resistance to freezing is imperative for the diver. The MK25 EVO regulator uses SCUBAPRO’s new Extended Thermal Insulating System (XTIS). The SCUBAPRO MK25 EVO first stage regulator meets the new EN250-2014 requirements for cold water diving, CE approved for 3360psi (230 bars). This model goes even beyond this super stringent qualification and has successfully been tested in extreme cold diving conditions at less than 36°F (2.2°C). The freezing resistance has been increased by 30% over the previous MK25 regulator first stage. SCUBAPRO has achieved this with some new design features. The new MK25 EVO has a proprietary thermal insulating coating on key internal components and an encapsulating main spring bushing that resists the cooling effect in previous MK25 first stage regulators, also; as a specific anti-freezing measure; our engineers have designed a patented finned cap with additional body fins for the MK25 EVO first stages for optimal-cold water diving. The fins (ribs) of the XTIS act as a radiator to increase the surface area of heat transfer from the water to warm up the internal parts that have been drastically cooled down by the gas pressure drop. The new MK25 EVO has a bigger body cap, a new body with insulating bushing and ribs, a new antifreeze cap patented isolation system with all internal parts fully insulated to improve cold-water performance dramatically.

The MK25 EVO is manufactured from marine grade chrome plated brass and offers a balanced composite/stainless steel flow-thru piston that would make any diver proud. It demonstrates SCUABPRO’s dedication to quality and creating positive diving experiences.