Use ultrasonic pulses to keep parasites, which are often the cause of asthma and allergic symptoms, away from your bed, carpets, and the entire house. The ultrasound particularly prevents dust mites from reproducing. The device operates without chemicals or fragrances. The ultrasound works at a frequency of 40 kHz, which is inaudible to humans and pets. The parasites are not killed but repelled, thus preventing their reproduction. The device is suitable for home use and can be powered through a socket (220 V). The effective range is 90 m³, equivalent to a room of approximately 36 m².