2 x Pestbye Battery Operated Cat Repeller V2 - Easy To Use Ultrasonic Cat Scarer with HyperResonance Frequency HyperResonance Frequency system - most effective frequency system to repel cats and other animals Large cover area - affects ground up to 32ft away Reliable PIR motion sensor - integrated into the repeller at just the right height Easy to use - simply insert batteries and push into the ground Detects and repels cat all-in-one method - no need for backup systems