Anti Rat Prank description

Anti Rats !
No chemicals, but an ultrasound emission disturbing unwanted guests and forces mouse to ... turn away!
This works by emitting ultrasonic (17-22 kHz) repellent for mouse that disturb the rats but not humans.
The only app with the right frequencies for mice.
Protects your house.
Safe and not harmful.
Note: frequencies 17-22 kHz can not be heard by humans. In this application the sound is mixed to be audible even to humans without losing their effectiveness.
We are investigating and trying to develop a rat repellent use better days and so having your attention. Thank you!