Just a note to tell you how well the HVAC Odor Block Commercial is working for us. We are using it in restrooms and utility rooms and other areas that have problematic odors. It has also been effective in absorbing odors within the air distribution system. Just put it in the blower compartment of the furnace or air handler and it removes odors and refreshes the air. Our customers who are pet owners love it, especially next to the litter box.