The air-balanced diaphragm MK17 EVO delivers constant and effortless airflow, and its internal system is completely sealed off from the elements, ensuring trouble-free operation no matter how cold or murky the water gets. This first stage is preferred by many cave and wreck divers who commonly find themselves in highly silted environments.

DRY AMBIENT PRESSURE CHAMBER
Increases freezing resistance, ensuring consistent airflow in the coldest conditions.

ENVIRONMENTALLY SEALED SYSTEM
Prevents water and pollutants from fouling the inner mechanism.

HIGHLY EFFICIENT INTERNAL DESIGN
Allows more airflow from its high-flow LP ports that are specially configured for better
hose routing.