The LED light will illuminate, which indicates the device is working.One pest repeller can protect 80-120sqm. 1 x Ultrasonic Pest Repeller. Ultrasonic Technology. Also, outdoor insects and rodents won’t enter your house, too.Eliminates Mosquitoes, Mice, Spiders, Ants, Flies, Roaches, Bugs, Fleas, Rats, etc.
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