"High-pitched frequencies deter cats, dogs and other animals from invading your space. Great for keeping raccoons away from the garbage. The signal is inaudible to humans but animals find the signal uncomfortable and leave. Other devices emit a constant sound, but Animal Away saves batteries with its infrared motion activation. Removal Of Multi-animal, Material Type Sealed temperature resistant PVC, Includes Infra-red motion detection, Product Style Repellent, Dimensions L x W x H in. 5 x 3 x 4, Power Source 9V, Single, Pair, or Set Single, Indoor/Outdoor Use Indoor/outdoor. Saves batteries by utilizing a motion detector that activates the powerful 23,000 Hz signal only when an animal approaches within range Mounts on wall, fence or even wooden stake"