The MK2 EVO is the only downstream piston-style first stage with internal components specifically designed to resist freezing in extreme cold water conditions. So you can expect top-notch breathing performance whether you're reef diving the Caribbean or wreck diving the Great Lakes.

Features:

• Classic downstream piston design features a chrome-plated brass body with one high pressure and four low pressure ports.

• Patented XTIS (Extended Thermal Insulating System) fully isolates the mechanical elements from the cold, increasing freezing resistance by an average of 50% over its predecessor without compromising breathing performance.

• Additional internal technical improvements include a spring insulating bushing and coating, an insulating piston bushing, an insulating sleeve and antifreeze cap, all of which contribute to the increase in freezing resistance.

• First stage is 3.5mm smaller than its predecessor but houses an oversized piston by 1.6mm that provides better breathing performance by increasing airflow by 15%.

• Stainless steel removable orifice allows for easier maintenance while extending regulator life.