2021 Best Ultrasonic Pest Repellers, Drive the Pest Away Quiet and Effective - If you're considering a non-chemical approach to pest reject, we recommend the Ultrasonic Pest Repellers are devices that emit a consistent noise at a frequency which is too high for humans to hear. These sound waves are designed to distract, annoy, and deter common household pests such as roach, spiders, mosquito, ant, and rodent. Intelligent multi-frequency ultrasonic conversion system make pests nowhere to hide. More Safe for Child & Pets - Ultrasonic sound is inaudible to humans and household pets,environmental friendly alternative to dangerous poisons and Sprayers, chemicals and traps, no bad smell and Corpses Easy to Use - Just plug the electronic pest control ultrasonic repellent in power sockets; It will start to repel the pests when the blue light on Noiseless - The ultrasonic waves that this repeller sends are far beyond the hearing range of human-beings. Enjoy a peaceful & pest-free tight sleep without any concerns for noise, keep your family have a good sleep form the noise. We are Here for you - The typical results can take 1 weeks depending on the severity of the pest infestation. Mostly can see the electronic pest repeller results within 3-4 weeks! Then we can say goodbye to pests and mice!