The MK25 EVO first stage with an air-balanced piston offers excellent resistance to freezing and superb inhalation sensitivity. The full-metal A700 combines excellent breathing performance with a real muscularity in design.

The Benefits of Piston Technology

The task of a first stage regulator is quite simple: reduce the high-pressure air owing from the tank to a consistent intermediate pressure for delivery to the second stage. The best way to accomplish this necessary step-down process is with an air-balanced piston-style first stage, the first choice of demanding sport divers and professionals.

An air-balanced piston first stage like the MK25 EVO offers excellent reliability thanks to fewer moving parts, and is more responsive for instant delivery of air on demand and extra-high air flow—especially in low tank pressure ranges.

Air-Balanced Flow-Through Piston MK25 EVO First Stage

The MK25 EVO first stage provides instant delivery of air on demand in all diving environments and all water temperatures. The inner mechanism is insulated from the environment, improving cold-water resistance and delaying ice formation.

The opposing HP ports allow the MK25 EVO to be positioned either up or down. The five high-flow LP ports provide higher airflow than standard low-pressure ports and are mounted on a swivel turret to maximize hose routing options.

A700 Second Stage: Muscular Design, Unparalleled Breathing Performance

With its striking all-metal casing, screw-down casing cover, and metal valve housing, the precision hand-crafted A700 second stage features air-balanced valve technology, a stainless steel inlet tube, and an oversized exhaust valve that deliver an unmatched ease of inhalation and exhalation.

Able to withstand years of aggressive diving, the rugged, full-metal A700 second stage case construction enables the use of a larger diaphragm inside a compact casing, increasing breathing sensitivity. The air-balanced second stage valve smoothes out the inhalation effort when diving at varying depths and supply pressures. User controls include a diver-adjustable inhalation effort knob and coaxial Venturi-Initiated Vacuum Assist (VIVA) switch.