Link together as many devices as you need with new SmartLink technology and protect every sized space with this complete pest control system. This innovative technology uses Radio Frequencies to link together repellers within 200m and allows for quick communication with low power usage, making it more effective for longer. This repeller combines ultrasonic sounds, inaudible to humans, and flashing lights that are activated by a motion sensor to create an unpleasant environment for the cat that will force it to move on and learn to avoid your garden for good.