I don't know yet if this works. I recently received it and it says that it takes up to 2 weeks to see results. The box and the information paper that came with it does not explain if the red light should be on at all time. 5 of the plug in devices have the red light on and 1 has the light off. I plugged the one device into other outlets and red light is still off. I guess is broken. I tried to contact the Customer Support and there is no phone number or email to reach someone. The only option is to return the product (yes, Groupon offers free returns) but is very inconvenient as I do need it now and I only need 1 plug replaced. Replacing all 6 devices might take 2 or 3 weeks.