We haven't seen any signs of mice since we plugged in the units.

We live in the country and have mice and squirrels running through our yard frequently. About two months ago, I was sitting at our computer and heard a scratching sound. A mouse was coming out of our a/c floor register. A couple of days later, we could hear a mouse scratching in one of our cupboards. I immediately ordered the Pest Repeller Ultimate AT, after reading many good testimonials. I ordered several for the house, and I also ordered one for my husband's storage building. We haven't seen any signs of mice since we plugged in the units. We keep birdseed in the storage building and have been particularly impressed that we haven't had any mice in the unit. I would strongly recommend these units. We had tried other brands in the past, but they just weren't effective. We certainly won't be without these units in the future.