12v Mushroom Roof Vent Caravan Motorhome Boat Comet Electric Fan VentilatorMushroom Roof Vent Caravan Motorhome Boat Comet 12v Electric Fan VentilatorMushroom style vent suitable for caravan /motorhome replacement or self build.Airflow: 60m3/hDiameter: 200mmVoltage: 12v dcWattage: 7wHeight above roof: 75mmRoof cut out: 95mmMin roof thickness 25mmSuitable for most Caravans, Boats and Motorhomes(No screws provided)