Due to the solid walls that will weaken the effect of the ultrasonic wave, we suggest using 1 unit per average-sized room with a pest problem. Smarter Protection: Adopting the latest ultrasonic chip to impact mice, rats, spiders, fleas, cockroaches, ant, flies, mosquitoes, the non-stop sonic waves target pests' auditory and nervous systems, making the house uncomfortable for pests without affecting humans and pets.
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