The Ozzie Mozzie is Brilliant !! I have two in a very large room. They are on all the time, but at Night is when it really comes into action. As soon as I turn in I switch off the lights and within a minute or two, Crack! first victim is electrocuted then followed by a few more eliminating all flying insects. The crack! is a little noisy, but I enjoy counting them (best so far is 7. ) At peace I slip into slumber.