"Solar vents provide mechanical ventilation utilising solar energy. The solar panel activates the fan, which allows the air to flow in. These autonomous vents detect water flows from waves and rain, while refreshing the atmosphere even on those calm windless days. Special balls inside the vents are pushed by the water to shut ventilation holes and ensure impermeability. They have two functions; one function activates solar function and the other modifies the fan’s function from clockwise to counter clockwise. Solar vents are made of white plastic, while the 98681 vent is equipped with an inox cover. Impermeability Water pushes the special balls inside the vent to shut ventilation holes and ensure absolute impermeability Solar panel Operates with Solar Energy. Activation with on/off switches"