This is the Scubapro MK25 EVO/G260 Scuba Diving RegulatorFeatures: 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) thermally insulates the inner mechanism from the environment, improving cold-water resistance and delaying ice formation in extreme cold-water conditions without compromising breathing 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. Four high-flow and one axial super 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. Air balanced second stage valve smoothes out the inhalation effort at varying depths and supply pressures. Rugged reinforced technopolymer design features SCUBAPRO's largest second stage casing and diaphragm for the ultimate in breathing sensitivity, regardless of position in the water. Metal components (inlet tube, orifice, inhalation control knob and hose connector) increase resistance to freezing when diving in extreme conditions. A diver-adjustable inhalation effort knob fine-tunes air delivery to suit changing depths, water conditions and personal tastes, and a Venturi-Initiated Vacuum Assist (VIVA) dive/pre-dive switch prevents free flows in cold water or when used as an octopus. High-flow exhaust valve reduces exhalation for better overall breathing comfort, and the reversible hose attachment allows you to easily adjust hose routing for tech diving configurations. Super-flow hose features an oversized bore that allows more air to flow on each inhalation. When you team SCUBAPRO's flagship first stage with a second stage engineered to excel in harsh conditions, you get a system that any recreational or technical diver can take on any dive, anywhere in the world, and be assured of rock-solid performance and reliability. The MK25 EVO/G260 is just such a system. The MK25 EVO delivers an ultra-fast breathing response, great sensitivity and extra-high airflow, making it the ultimate do-it-all first stage for all water temperatures. The G260 is the most imitated air balanced second stage of all time. It features metal internal components and a left-right hose attachment option, making it a great choice for tech diving configurations and a consistent top-of-the-line performer. "
