The Tickless/SonicGuard device emits a series of ultrasonic pulses that are imperceptible to humans,
pets or wildlife, but interfere with the ability of ticks and fleas to orient themselves.
The ultrasonic wave is an acoustic (sound) energy in the form of waves
having a frequency range above that of human hearing range.
The sounds humans can perceive have a frequency ranging from 20–20,000 hertz (Hz).
While pets can hear ultrasound frequencies, 40 kHz is already over their hearing range.