Keep critters out?? Also, it does help keep some of that Texas heat from radiating INTO the belly area.
I am sure there are other ideas on this, and, seems to me that I remember some one saying you could buy replacement stuff?? somewhere?? Lowes?? and they even had a product name.
You could try a search, but, the info may be buried in the archives???
well, what a lot of help this post is!