This is a V V Star Top portable evaporative air cooler featuring mechanical controls.Cooling Method: It uses a water circulation system to reduce air temperature through evaporation.Controls: The unit has a mechanical control panel with knobs and buttons to adjust fan speed and other functions.Capacity: Similar units generally feature water tanks ranging from 15 to 60 liters.Energy Efficiency: Evaporative coolers typically consume less energy than traditional refrigerant-based air conditioners.