Instruct: Classify a given Amazon review into positive or negative sentiment.
Query: Does not work!

I had bought a similar product at a dollar store and was impressed with how many bugs it killed. When that one died, I ordered 2 of these. When it arrived, I put batteries in and tried it on a swarm of fruit flies. They went right through! Not a sinle zap. I tried the other with the same result. It seems to be able to zap house flies but nothing smaller. A total waste of my money.