Works as designed, however on battery, it is barely a breeze.
I plug it to our generator to charge the internal battery so no wated money on D batteries.
Still, its nice to have the D battery option (in case of emergency).
The smart feature of the fan is that it will run on whatever power is available if its plugged in ot will run on that, or it will go to the internal lithium battery or as a last resource will go to the D batteries.
Also keep in mind this is a 10” fan; most battery operated fans in Amazon are 5”.
Just had first opportunity to try to use this fan at a dog show AND if does not stay charged up for more than 15 minutes after being left to charge for `12 or more hours.
Very disappointed and would like to talk to a person regarding poor product that cannot be charged up and used without having to put new batteries in it all the time.
Fortunately, I had time to return for full refund, so that is what I did.I instead opted for a fan from another manufacturer with better reviews.
I have tried charging it fully before using it, leaving it plugged in and everything but it only continued to do this more and more over time.
At this point, 15 months after I bought it, the fan has trouble working even on A/C power.