May not work for many but it works for me. Netting is 3/8" X1/4" opening so it has to be a small chip to make it through. Lots of meshes are available in garden and pond, even down to mosquito. Installed conduit in a U shape. Only one I hook in the center is all that is needed for this weight. Ties back against the wall when not needed.
Like John, lets the air through for heat and cooling.
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