This mobile rodent repellent works with the latest high frequency technology ultrasound and without any installation the rodent repellent can be used everywhere eg in car carport garage and house ideal for protection of cars parked for a long time the optimum maintenance free performance of 12 months can be achieved only with high quality alkali manganese batteries the device must naturally be mounted in such a way that no water or dust can penetrate in the casing can also be used