I had it on for a couple of nights and noticed no difference.
Then I saw a review suggesting leaving it on 24/7, so I did that.
10 days later - not a mosquito or midge in sight!
Absolutely amazed.
My husband is allergic to midge bites and literally has scars all over his legs. I am sure noone gets bitten more than him, but he has not had a bite since!
We have it next to the pool and we have bush in our backyard. Table height as the customer service team suggested.
Truly amazing. A+++