The Top Damper is now available with the additional protection of abuilt-in Stainless Steel Cap. It comes completely assembled as one unitand it’s called the Top Damper Plus! When closed, the Top DamperPlus seals out rain, snow and sleet while sealing in “paid” heat andair conditioning. When open it has the protection of a conventionalchimney cap. Gain the added benefit of a cap and lose none of thefunctionality of the Top Damper.