The MiniVent 1000 is the smallest and most economical solar vent in the Nicro line. At just 7" in diameter and approximately 1-3/4" high, the MiniVent 1000 is compact yet effective. The solar powered model is an exhaust vent only, but it will keep the boat cabin cool when you need it most - during the hot sunlight hours. Under solar power the MiniVent 1000 will move 700 cubic feet of air per hour. At night, even a light breeze will continue to ventilate the boat passively. Built-in shut off damper prevents water intrusion in rough seas. Fits a 3-3/4" installation hole.