Prevent air leakage in your inline fan setup with a backdraft damper by S&P. These backdraft dampers are made out of steel and are designed for vertical or horizontal mounting. Made of galvanized steel, the backdraft dampers have lightweight aluminum damper blades and are spring-loaded for positive closure. The backdraft dampers are easy to install and are an important part of installing a duct fan setup. These dampers install inside the circular ducting to prevent a backdraft of air when the fans are switched off.
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