The light up indicators let me know that it's working. I can put it anywhere in my home that I have an issue. In my case it's mice. Since I live beside a farm we have issues with mice around here. I hate it so much.This Ultrasonic Pest Repeller was super easy to set up. All you do is plug it into the electrical outlet and switch on the appropriate switches. I am so happy that this product we can not feel or hear while it's working. Plus the fact it doesn't hurt or bother our animals in the house. It leaves me peace of mind knowing that I can have this around my family and my pets. Biggest benefit is chemical free and we don't have to worry about finding dead animals in the house. So far I don't have to worry about anymore unwanted pests in our house. More info listed below about 

Brillante Ultrasonic Pest Repeller for Electronic Home Insect & Rodent Control

• REPEL PESTS FROM YOUR HOME'S WALLS - This electronic pest repeller features electromagnetic technology to disturb pests hidden in walls and deter undesirable would-be invaders by slightly varying the electromagnetic frequency of the in-wall wiring without impacting other electronic equipment.
• NON-TOXIC HOME PEST CONTROL - Helps you maintain a pest-free home without the use of poisons or chemicals should you wish to avoid them. Control rodent and insect invaders with ultrasonic sound frequencies (inaudible to the human ear) and electromagnetic fields instead of chemical sprays and poisons. Use to target your mouse problem or to deter bats, ants, cockroaches and other crawling insects.
• CHOOSE THE FUNCTIONS YOU WANT - This pest repeller includes 4 switches that let you select which of the 4 functions you want to activate. For example: It's easy to switch off the ultrasonic mode if you intend to place the repeller near sensitive pets like rabbits, hamsters or gerbils. Subtle LED lights indicate which features are active.
• ELIMINATE ODORS & GERMS - Use the negative ion and O3 functions to help eliminate odors, airborne pollutants and to reduce virus and bacteria levels. Use in conjunction with other non-toxic methods such as essential oils to amplify the effect.
• EASY TO USE & RISK-FREE GUARANTEE - Just check the manual for recommendations, plug into a standard wall outlet and activate your desired function for indoor pest control. Ultrasonic for rodent defense and insect repelling, electromagnetic for in-wall pests and negative ion and/or O3 for airborne microbe control. If you don't get the results you want we'll fulfill our 60-day no-hassle refund guarantee

****Received from Tomoson for my unbiased opinion 

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