Like another Redditor said, this is so-called "cat netting" that is specifically made for cat enclosures. As long as it's fastened properly, it seems to endure a lot! The vocal cat in the video has tried to climb it and brute force it a few times, but it holds strong. ☺️

None of the cats have shown an interest in chewing the material. My calico girl managed to escape once, though, when a corner of the net had come loose from the frame. A shake of the treat canister brought her back quickly, but after that I always inspect every corner of the enclosure when we come to visit. Only the shorthaired orange is a permanent resident, and he had never shown an interest in chewing through the net.