Do you have wind-related chimney draft problems? This is the premier chimney cap for solving common, wind-related chimney draft issues! Wind-induced downdrafts cause smoke to enter the home when tall trees, mountains, hills, or tall buildings are near. The Vacu-Stack chimney cap not only helps with draft issues, but it also protects the chimney from debris, animals, rain, and snow from entering the flue. Fits inside of your chimney pipe. Use the Vacu-Stack chimney cap with solid pack Class A or single wall chimney pipe. Manufactured with 304 stainless steel in the USA. Have questions about this product? Please ask, we're here to help you do-it-yourself!