Eco-Friendly Ultrasonic Pest Rejection is the perfect way to remove pests from the soil! However, keep in mind that the nature and density of the ground will affect the performance of the repeller, so check the ground before installation. Solid ground provides the best sound transmission. Frozen, watered down or puddled soil will cause this device to work poorly. It is solar powered and is impenetrable for all unwanted visitors 24/7. Sound waves attack the mouse's auditory system and nervous system and stimulate its brain. OUR GUARANTEE We are confident that we offer some of the best products on the market. Therefore, we provide a 30-day guarantee. We will make every effort to ensure that you are completely satisfied with your purchase. Online shopping can seem daunting. We want you to know that there is absolutely zero risk of purchasing something. We won't make it difficult if you don't love it. We offer email and ticket support 24 hours a day, 7 days a week. If you require assistance, please contact us. Please contact customer service if you have any problems with your purchase.