What a great fast any easy pen. We use pallets since we get them for free and only have to pay for screws. My concern with this type of pen would be the corners stability to protect from predators. So far our pallets have worked but have to be changed out and checked frequently.
Yeah, these are already in the perimeter fence as well, so the real predators like bears, mountain lions, coyotes and wild dogs shouldn't make it this far...