We now use this for top mount dampers and it is a great product. We use this brand for its fair price and ease of installation. It uses a cap/screen-spark arrestor with it, meeting NFPA 211 code requirements, other brands do not. It comes in a variety of sizes and is made with stainless steel and comes with a manufacturers lifetime warranty. It will reduce heat loss in the heating season and according to one of our customers it greatly reduced her heating and electric bills.