I have x-pens and NIC cages.
Ringo is in an NIC pen do to his special needs. It is 5x2 though that will be changing soon.
Elvis is in a Dog Exercise pen because he chews plastic. He brought down two NIC cages on himself. Sheet on top because he climbs and jumps out. Metal cake pen for litter pan cause he chews the plastic ones.
I have also used pens for other reasons and for fosters sometimes. Here are NIC ones.
This was a big one for playtime while I cleaned.
One for bonding.
This is other metal ones I used for different reasons.
Also have one that I can attach to the cages for when I am to busy to let them run around.