we live in the country and regularly fight mice. husband decided to try those sonic mouse repellants. He forgot he spent fifty bucks on them a year ago. They didn 't work thenm, though I was not home when he tried them. . Now they do. ON ME!! He plugged one in this evening after I was done in the kitchen. Just a second ago I went to heat up my rice bag and OMG!! My ears plugged up with air pressure and HURT, my entire head is buzzing, and all I could do is cover my ears but it didn't help. i just burst itno tears. My vision even went a bit wonky and it felt like my head would explode right there! Unless I am planning to visit (& you don't want me to!) or you want to drive someone else away, my recommendation is to stay AWAY from the sonic noise pest repeller gizmos!!! This is AWFUL!!!