This filter is truly amazing! The cold air return is a short distance down the hallway from my laundry room, where the cat litter boxes are. I couldn’t figure out why I could smell the litter, even though it was cleaned daily, all through the whole house. Then it dawned on me, the return was pulling the air from that room. I would spray Lysol in the filter, I hung deodorizers, I even tried dryer sheets. Then, I saw the ad for this filter that supposedly helped with odor. So, I thought it c...