Wish I had searched for this article before I bought a ball. I purchased two of them and both of my hedgies panicked. I felt so bad! One panicked immediately and pottied and the other froze in a half-ball, refused to move. I waited with him (Whyte) to see if he just needed to warm up to the idea but his body-language was very stressed so I took them both out of their balls. Could have saved myself and them the stress and money, oops! Then I thought maybe they just needed a larger clear ball but after reading these posts I wont bother. Thanks.