At 26 each a filter change is over fifty dollars if one was to change filters at the recommended 18 mosthe cost at 6 yrs would amount to 350 or less than 5month

I use it in the room where my two cats have their litter box and it works well to keep the odor under control as long as i have the window open a crack and it does controls litter dust but not to the point that i no longer need to dust