I really wanted this product to work.  After using this product for an entire season I can not recommend it.  I initially reported the fan noise wasn’t an issue but I later discovered it was on low.  On the high or treeestand setting it is very loud.  Loud enough that deer will look up for the noise.  I used the Ozonics for several weeks without having a deer come downwind of me and I began to wonder why was I bothering with carrying this thing back and forth to the woods.  I never hunt a stand with the wrong wind so I quit carrying it.  Then i sat in what I call an observation stand and several deer came in downwind of me.  So now I have a use for the Ozonics when I sit an observation stand and I’m not sure of the deer movement.  A few days later I put up an observation stand and take my Ozonics.  About an hour before dark a group of 5 doe come out the ridge and are going to pass on the downwind side.  There was a very slight breeze a perfect test for the Ozonics.  Just as soon as the lead doe hits my scent she does a 180 and runs off snorting.  Over the course of the year I had deer pass downwind completely unaware and I also had deer blow for no apparent reason.  Although this isn’t enough evidence to prove Ozonics doesn’t work I have concluded that it isn’t for me.  My best advice is to use the wind.