| Product Image | Series | Name |
|---|---|---|
 | 4500-3000 OBD and 4550-3000 OBD Series | Combination Stationary Outside Air Louver with Opposed Blade Air Control Damper |
 | 4500-3000P and 4550-3000P Series | Combination Stationary Outside Air Louver with Parallel Blade Air Control Damper |
 | 4500-3510 and 4550-3550 Series | Combination Louver with Pressure Relief Damper or Backdraft Damper |
