I know it is too small for 4 boars. I am working on a second 2x3.5 cage for the other 2....so there will be 2 boars in each cage. That is to come in the next few weeks wish me luck. This is the first cage. It is bigger than the cage they were in before so they are very happy! I can only imagine once I get the second cage up they will feel like they are in paradise!