An air duct for a refrigerator fan.

An air duct for a refrigerator fan. Originally, there's no air duct, which results in the air just being swirled around. There's no real airflow. This duct ensures proper airflow to the heat exchanger, allowing it to operate more efficiently. It probably also fits other standard refrigerator fans. This one is from a 2014 Pepsi cooler. The fan blades need to be sanded down by at least 1-2 mm using a belt sander.