STELLAR BREATHING PERFORMANCE, OUTSTANDING RELIABILITY
The ultimate go-to air delivery system for cold water or technical diving.
When you team SCUBAPRO's flagship first stage with an air-balanced second stage engineered to excel in harsh, cold-water conditions, what you get is a regulator system that any hard-core recreational or technical diver can confidently take on any dive, anywhere in the world, and be assured of rock-solid performance and outstanding reliability. In other words, the MK25 EVO/G260.
The MK25 EVO first stage lets you enjoy an ultra-fast breathing response, instant delivery of air on demand, great sensitivity and extra-high airflow -- regardless of how cold the water is. This is made possible with SCUBAPRO's exclusive patented Extended Thermal Insulating System (XTIS) that fully isolates the mechanical elements of the first stage from the cold, increasing its freezing resistance 30 percent over previous versions of the MK25 without compromising breathing performance. This makes the MK25 EVO the ultimate do-it-all first stage for all water temperatures.
The G260 is the most imitated air balanced second stage design of all time. First introduced in 1986 as the G250, it was the first regulator to introduce an adjustable Venturi Initiated Vacuum Assist (VIVA). Today's modern version features metal components (inlet tube, orifice, inhalation control knob and hose connector) for excellent cold-water performance. It also offers a left-right hose attachment option, making it a great choice for tech diving configurations.
Of course, you don't need to dive in cold water or find yourself in extreme diving conditions to fully appreciate the powerful yet easy-breathing attributes of this reg system. But if you're a demanding diver you can rest assured that with every breath you take, the MK25 EVO/G260 will deliver effortless airflow and consistent top-of-the-line performance.
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Unterwasser Test Winner - Cold Water Reg -- April 2015
MK25 EVO First Stage:
- Air balanced flow-through piston in a chrome-plated brass body provides constant and effortless airflow unaffected by depth, tank pressure, or breathing rate.
- Patented XTIS (Extended Thermal Insulating System) fully isolates the mechanical elements from the cold, increasing freezing resistance 30 percent over the previous MK25 without compromising breathing performance. Key insulation system components are visible in blue.
- New spring insulating coating, body insulating bushing, anti-freeze cap, bigger body and cap thread all work in concert with the XTIS to improve cold-water performance.
- Anti-freeze protection radically increases breathing reliability when diving in the most extreme water temperatures.
- Two opposing high pressure ports allow the first stage to be positioned either up or down.
- Five high-flow low pressure ports on a swivel turret maximize hose routing options.
- External intermediate pressure adjustment enables technicians to fine-tune performance quickly and easily.
- Available in either 3364psi/232bar INT or 4350psi/300bar DIN configurations.
- Weight: INT 232 (oz/g): 27.9/790; DIN 300 (oz/g): 20.1/572.
- Airflow at 2900psi/200bar: (l/min/SCFM): >8500/301.
- Intermediate pressure (psi/bar): 130-142/9.0-9.8.
G260 Second Stage:
- Nylon fiberglass design features SCUBAPRO's largest second stage casing and diaphragm for the ultimate in breathing sensitivity, regardless of position in the water.
- Metal components, including metal air barrel and metal valve inlet tube, increase resistance to freezing when diving in extreme conditions.
- Air-balanced valve smoothes out the inhalation effort when diving at varying depths and supply pressures.
- High-flow exhaust valve reduces exhalation for better overall breathing comfort.
- Diver-adjustable inhalation effort knob fine-tunes air delivery to suit personal tastes.
- Venturi-Initiated Vacuum Assist (VIVA) dive/pre-dive switch prevents free flows in cold water or when used as an octopus.
- Reversible hose attachment allows you to easily adjust hose routing for tech diving configurations.
- Super-flow hose features an oversized bore (larger inside hose diameter) that allows more air to flow on each inhalation.
- Ultra-comfortable orthodontic mouthpiece is easy to grip yet doesn't inhibit airflow.
- Weight: 9.7oz/275g.
- Airflow at 2900psi/200bar: 1800 l/min - 64 SCFM.
- Maximum low pressure: 203psi/14bar.
WORK OF BREATHING
Work of breathing depicts the cycle of inhalation and exhalation energy expended to breathe from a regulator.
Inhalation is the effort to open valve and maintain airflow.
Exhalation is the effort to push exhaled breath through the regulator casing and past the exhaust valve.
So, the lower the better. SCUBAPRO regulators exceed WOB standards of both the US Navy and European CE.
EN250 standards for a cold water regulator mandate a limit of 3.0 Joules per Liter
at a depth of 50m, with 300bar of tank pressure, 2° to 4° C water temperature and
25 breaths per minute.