Review (1/5): Won’t shut off so burns thru batteries.  Useless.....
With new batteries, this works great! But the batteries kept running down after about 48 hours. I’ve since figured out the ionizer stays on all the time even when the switch is “off”. I can hear it buzzing and the buzzing stops when I pull the battery. So it is pretty much useless if I have to install the batteries every time I use it. Definitely not worth $20!