These are excellent quality back draft dampers. They are made from heavy-gauge galvanized steel with heavy duty springs. They use both an embossed bead & rubber gasket to help keep ducting securely in place. They prevent back draft air when your fans are off.
Value Quality Pricejameson 2016-03-01This damper is well made heavy gauge sheet metal / with built in gasket ! better made than most I've used and at half the price of otherr store. Worth ever penny as it seals tight