Bumper Functionality:
Adapt to the shape of the filter box when closing the Air Manager hood and limit all kinds of leakage that can be induced by flow differences between the outside and the Air Manager. The bumper seals the interface between the filter box and the hood.
Ductless Adapter Functionality:
Mounting plate to secure the bumper.
The author remixed this model.
Original model – I made it. CAD available at onshape.com