Scubapro MK25 EVO/S620Ti Regulator Set (Yoke)

Scubapro has been the Leader in the Evolution of piston controlled first stages since its beginning; the MK25 EVO carries on this heritage with an array of patented features ensuring unfailing performance.

The MK25EVO is a balanced piston first stage, Scubapro’s absolute top performer. It is a superior regulator thanks to its ultra-stable intermediate pressure (IP) resulting in an extremely-punctual and constantly high delivery of air. This means instant airflow at any tank pressure and water temperature for a real carefree dive.

Air Balanced, Flow-Thru-Piston-First Stage: Air balanced pistons deliver significantly more air to the second stage than any other first stage, while 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 air flow, especially in low tank pressure ranges. The tired diver benefits from a smoother breathing regulator during 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.

The MK25 EVO has two opposite high-pressure ports (HP). The arrangement of high-and-low-pressure hoses is crucial to diving comfort. Two opposite 7/16″ threaded HP ports allow for an individual positioning of the first stage (pointing up or down). This allows the diver to position the gauges either on the right or left side and increases the freedom of movement for head and neck. Multiple 3/8″ threaded low-pressure ports (LP) – For ultimate freedom in the arrangement of LP hoses, the MK25 EVO accommodates five HF (High Flow) ports on a swiveling turret, which allows for 360° swivel of hoses. High flow ports deliver about 15% more air than conventional ports. Externally adjustable intermediate pressure- allows authorized Scubapro service technicians to quickly fine-tune and adjusts the first stage after maintenance without the need to disassemble it.

Cold Water Diving conditions can be drastically 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 3360 psi (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 resist the cooling effect in previous MK25 first stage regulators, also as a specific anti-freezing measure; Scubapro 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, new body with insulating bushing and ribs, new antifreeze cap patented isolation system with all internal parts fully insulated to dramatically improve cold water performance.

This system now gives the diver superior cold-water performance, equal to that of Scubapro’s MK17 first stage. Now you have the option of a high-performance flow through piston design, with a high level of performance in cold water. This is the answer for those divers who demand a high level of performance for cold water environments. 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 Scubapro’s dedication to quality and creating positive diving experiences.

Scubapro teams its high performance first stage with a brand new air-balanced second stage. The new S620 Ti embraces the best features of Scubapro’s renowned S600 in an upgraded, state-of-the-art design. Smaller and lighter than the S600 but using the same-sized diaphragm, the S620 Ti delivers excellent performance; work of breathing has been reduced by 37% over the S600, providing effortless airflow under all dive conditions. The full titanium inlet tube is ultra-light, the large purge button improves water circulation, and the new exhaust tee increases performance while directing bubbles out of the field of view. In all water temperatures, in all dive conditions, this new regulator system is a winner. Because of the S620’s versatility, it can meet the diver’s needs as frequently as the diver changes dive sites. The S620 valve housing is constructed from lightweight titanium. The S620 has a linear air-balancing valve, and a top-notch air-balancing system. This regulator’s air-balanced linear-flow valve allows the diver to use less energy while breathing underwater; it makes breathing during a dive as simple as well, breathing in and out!

The S620 air balanced high performance second stage, is Scubapro’s performer. Rugged reinforced techno polymer case and front cover with stainless steel frame looks good plus is able to withstand years of aggressive diving. Regulator has a diver adjustable inhalation control that enables personal adjustment of breathing effort. Diver adjustable Venturi Initiated Vacuum Assist (VIVA) dive/pre-dive control switch and extra high flow exhaust valve account for easy inhale & exhale. Scubapro uses a comfortable orthodontic mouthpiece on every second stage to reduce jaw fatigue and gum irritation. It was developed by dentists and dental laboratories and lasts longer than any other mouthpiece, because only a minimum effort is needed to hold it comfortably in place. The regulator comes equipped with a super comfort high-flow (HF) mouthpiece for smooth air delivery. The Regulator weighs 32.2 oz. (913 g), comes with an oversized bore super-flow 3/8″ threaded LP hose and an owner’s manual.


Scubapro MK25 EVO/S620 Ti Regulator Set Features:

  • Scubapro Performance and Reliability
  • Weight: 32.2 oz. (913 g)
  • Owner’s Manual

Scubapro MK25 EVO First Stage Regulator:

  • Cold Water Performance Equal to Scubapro’s MK17 First Stage
  • EVO: Evolution, Revolutionize Existing Technologies to Higher Performance
  • High Performance, Reliable Scubapro Technology and Value
  • Superior Ultra-High Airflow System,
  • Maximum Performance in All-Temperatures & Conditions
  • Ultra-Stable Intermediate Pressure
  • High Performance in Warm and Cold Water to 3336 psi (230 bars)
  • Meets New EN250-2014 Requirements
  • CE Approved for 3360 psi (230 bars) in Cold Water Conditions
  • Increased Cold Water Efficiency by 30% Over-Previous MK25 Regulator

New Design:
Proprietary Insulating Coating On-Key Internal Components

  • Specific Anti-Freezing Measure
    Patented Finned Cap and Body
    Xtreme Thermal Insulating System (XTIS)
    XTIS Ribs: Like Radiator, Increase Surface Area of Heat Transfer
    Warms-Up Internal Parts

New Parts:

  • Bigger Body Cap
  • Insulating Bushing
  • Antifreeze Cap
  • Patented Isolation System
  • Internal Parts Fully Insulated
  • Dramatically Improve Cold Water Performance
  • Air-Balanced Flow-Through Piston Design
  • Balanced Composite/Stainless Steel Flow-Thru-Piston
  • HP Ports: Two 7/16″ Threaded
  • LP High Flow (HF) Ports: Five 3/8″ Threaded
  • LP Ports Mounted on Swivel Turret Cap for Maximum Hose Routing
  • Construction: Marine Grade Chrome Plated Brass

Halcyon S620Ti Second Stage Regulator:

  • Scubapro’s Top Performer
  • Unparalleled Breathing Performance
  • Diver Adjustable Inhalation Effort for Personalized Breathing Control
Venturi Initiated Vacuum Assist (VIVA):
Dive/Pre-Dive Control Switch
Prevents Free Flow in Cold Water
Decreased Inhalation Resistance
  • Materials: Titanium & Techno-Polymers
  • High Comfort Orthodontic Mouthpiece
  • Includes Super Flow Oversized Bore 3/8″ Threaded LP Hose


2nd Stage Design Balanced
1st Stage Type Piston
2nd Stage Series G Series
Water Temperature Cold, Temperate, Warm
Connector Type INT
Nitrox Mix Up to 40%
HP Ports 2
LP Ports 5
1st Stage Materials Chrome-Plated Brass
2nd Stage Materials Metal/Reinforced Technopolymer Casing