We use the wire xpens a lot. Occasionally we use a softsided playpen in the RV if needed, but we do put wire ties on the zipper openings to keep them closed because Shelby & Seeger know how to unzip them. Here is a pic of one similar to what we have. We bought ours from petsmart. I don't know if it would keep an escape artist from getting out... but it works for my 3 if we need it.
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