This is an ionizer that can be used at home OR in a car , where you have a USB port/adapter, or in the car with the supplied cable. I have it working in my house for 3 days. It's quiet and I can't feel anything in the air, but I didn't have any smells at first either. Sometimes they can emit a slight odor with ionizers, but not this one. You have to wipe the collectible plates every few weeks and they come out and fall apart. I don't spend enough time in the car to use it there, so I installedโฆ