STV Big Cheese Sonic Repeller 3 pin plug for use in the UK Entry-level pricing for the sonic category For use in a single room area up to 400 square feet (37m) Continuous output of over 100d B at swept frequencies too high for people, cats & dogs to hear Welfare-friendly deterrent that does no harm to rodents STV726 is an apparatus which can be used to repel rats & mice. To set the apparatus: Simply plug the Advanced Pest Repeller into a standard 3-pin uk outlet in the area affected by mice or rats. The red light on the front of the unit will light up indicating that it is functioning. To maximise performance: Leave the unit operating continuously. Make sure food is stored out of reach of rodent pests. Avoid placing the unit behind furniture or curtains. Find & repair any openings where rodent pests can get in.