Review on Imperial Premium Intake Built PA 4W by Dale Toth

Very glad I picked up and bought the vent cover from Home Depot. Most competing products have a one-way flow feature that blocks airflow from the outside to the inside. But what if you need internal air circulation, for example for combustion air in a fireplace? This allows both directions. What also made this work is that it fits perfectly and snugly into a 4 inch metal vent through a brick wall in my house. Other vent covers are designed to be installed during home construction. They fit on the outside of the vent. The round cylindrical surface that fit into the vent was so tight I couldn't squeeze it with my hand. But I found that the blind cover can be removed and snapped back into place. This was helpful because I could remove the blinds and gently tap the flat surface underneath with a hammer and a flat piece of wood. This will ensure the fan cover is snug against the wall and is secure enough that the forces of nature cannot rip it off. Then I could snap the slat front.