Twin power system - allows managing the delivery rate of gas from natural breathing to power breathing. By rotating the adjustment sleeve on the hose inlet, you can achieve VAD+ performance Metal 2nd Stage with PVD coating Adjustable breathing comfort is allowed with the breathing resistance control knob on the left side of the regulator. Optimum performance is delivered when the knob is turned all the way out (counterclockwise when looking at the knob) Pneumatically balanced second stage - with this system, the low-pressure air from the first stage is directed through a hole in the center of the second stage valve, until it reaches an air chamber located at the end of the valve. With the same pressure on both sides of the valve, the spring tension required to close the valve is greatly reduced. Lighter spring tension translates into reduced breathing effort. This in combination with the 2nd stage VAD which is automatically regulating air flow based on the divers demand, results in a high performance, highly comfortable, and natural breathing 2nd stage! High air flow Wide pivoting silicone purge button is very easy to purge Cold water use Superflex hose is extremely lightweight and exceptionally soft to guarantee the maximum freedom of movement and reduced jaw fatigue