I'm looking for a pool cover box accessory that I don't know exists for sure. I'm hoping some experts here can help. I have a flush mounted auto pool cover that has a 6-8 inch opening where the cover goes into the cover box and is wound around a spool. The 6-8 inch opening is not protected by anything so leaves, dirt, dust, etc can be blown into the opening and quickly fill the cover box. Also, when I retract the pool cover, any leaves and debris on the top is deposited in the box as the cover winds around the reel.

Now to my question: is there such a thing as a plastic type brush or plastic phalanges that you can fit across the opening of the cover box that would help stop leaves from being blown in or dragged into the box by the cover? I'm thinking of something you'd see in a car wash that hangs down loosely from the top that would not impede the cover, but would provide some blockage of debris going into the box.

Any ideas?