in the previous post, there was someone who posted, saying that medklinn is actually producing an ozone (which is not good for your lung), not ion.. but from my readings, all ionizer is actually produce an ozone as byproduct.. its just the reaction of producing an ion... but the important is, it should come in a very low quantity... same thing goes to sharp plusmacluster ionizer. so the statement that medklinn is producing ozone instead of ion is misleading. anyway, im not a medklinn seller... pls dont flame me. im just a plain guy looking for the best air purifier for my 2 year old boy suffering rhinitis...