I've tested many, many anti-mosquito items in my quest to bird without being bitten. The Coleman mosquito deleto actually seems to work reasonably well!
This device is maybe 6" tall and is cylindrical in shape. It's powered by two AA batteries and has a VERY quiet fan in it. You put the repellent (provided) in the bottom of the base, and turn it on. I swear I couldn't tell the fan was even moving until I held it right up against my ear, so it is whisper-quiet.
The box claims that it repels in a 100' radius. I certainly wouldn't agree with that - we still saw a few mosquitos in near us. But the volume of mosquitos did seem to be far less than usual. We had friends over and had a full dinner outside without being bothered much at all.
Of course, if you're out and about, you can't really carry this unit with you as you go. It's best suited for a sit-down situation where you can put the unit in the center of the table. It doesn't create a noticeable aroma, so it doesn't make the entire area smell of pesticides. Coleman says that the chemicals it emits interferes with the mosquitoes' ability to trace carbon dioxide and other human emissions that mosquitos follow.
I'd definitely give this a try in your environment and see if it does the trick!
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