This demonstrates why ferret owners must "ferret proof" their homes! This is Scipio wedged between the back of the cage and the wall behind it. He crawled there (from the top of the cage) all by himself. He was NOT stuck. (Though I thought he was at first!) I measured this gap and it was less than 1"! Fully demonstrates the fact that where a ferret's head will fit, so will the rest of him!!!