The All Season Control Cover is a patented, proven product thatshould provide years of reliable service. It will allow you to shutdown your chimney air tight until you are ready to use it. The AllSeason Control Cover chimney top damper is a vital element inoverall Homeland Security at the home level. If properly installed,it will keep animals, pests, fallout particles and biochemicalhazards from entering your home via the chimney top. It will alsoreplace rusted or worn out chimney dampers or fireplace dampers andmake fireplace repairs or chimney repairs much easier.