Made of galvanized steel. Prevents reverse air flow when fans are shut off. Saves CO2 and prevents odors from flowing backwards. Rubber gasket pre-installed on exterior for an air tight seal.
Listing created
Sep 14, 2021
Made of galvanized steel. Prevents reverse air flow when fans are shut off. Saves CO2 and prevents odors from flowing backwards. Rubber gasket pre-installed on exterior for an air tight seal.