The operating switch and indicator light of Wallas 1300 is located on the end of the heater, while other models have a separate control box (available as accessory to 1300). In models 1800, 2400 and 3200 the operating switch can be set at full, half or low power or fresh air ventilation. Wallas 1300 is ideally suited for heating one spacious cabin or the wheel house. Particularly low power consumption makes 1800 an excellent choice to sailing boats. Quiet and powerful models 2400 and 3200 are suited to larger sailing and motor boats.