| Backdraft damper, vertical mount, Model WD-330, 9 In Sq, No Flange, Performance up to 2,500 ft/min | $136.00 | | |
| Backdraft damper, vertical or horizontal mount, Model WD-410, 10 In Sq, No Flange, Performance up to 2,500 ft/min | $145.00 | | |
| Backdraft damper, vertical or horizontal mount, Model WD-410, 12 In Sq, No Flange, Performance up to 2,500 ft/min | $150.00 | | |
| Backdraft damper, vertical or horizontal mount, Model WD-410, 16 In Sq, No Flange, Performance up to 2,500 ft/min | $197.00 | | |
| Backdraft damper, vertical or horizontal mount, Model WD-410, 18 In Sq, No Flange, Performance up to 2,500 ft/min | $204.00 | | |
| Backdraft damper, vertical or horizontal mount, Model WD-410, 24 In Sq, No Flange, Performance up to 2,500 ft/min | $280.00 | | |