Aren't those balls dangerous for chinchillas? I had one once with a hamster and his really heated up after just 10 minutes of rolling around. Given than chins are so sensitive to heat I would think this would be a no-no for them.
It's a bit of an iffy topic...
I think that with proper supervision they can be a really fun toy for chins and a safe way to exercise. If the ball is big enough, if they're not left in for too long and supervised properly and if they don't get too hot etc. But a lot of people hate them and believe they are dangerous. 
The "roll-a-bout" balls are only as safe as the environment they are in and the close supervision of the caretaker of the chin.The "JUMBO" size is 15 inches in diameter and is the only size I would recommend ... if you want to use one.
{The "large" or "giant" are to small and will effect the growth of the spine.}
The temperature in the room is also a factor ... the cooler the room, the better.
If you have floor heating vents ... be very careful and block them so that the ball can not come to rest on or near a vent.
Unsupervised balls can get stuck under furniture ... roll out an open door and/or down a flight of stairs that are not properly blocked off.
Other family pets are often more than happy to help turn a little chin loose ...
... or be terrorised by it.
Play time inside the ball should never be more than 10 or 15 minutes ... depending on the activity, health health of the chinchilla and it's sensitivity to temperature.
Never use one outside ... they have been known to break open by themselves ... an event which would probably cost you your chin.
Even inside, sun beams shining through windows, can cause the temperature inside the ball to increase quickly.
A ball is not a chin-sitter ... if not properly and constantly supervised you can be lulled into a false sence of security ... it is a toy that can quickly become a death trap ... .
A rolling ball needs to be supervised even more closely than regular free play times ... you never know when to expect the unexpected.
A ball should be washed and dried, every time it is used and with each individual chinchilla. If not washed and dried properly, it becomes a breeding ground for germs and bacteria.
They are great when used properly and not as a substitute for your personal attention.
Jo Ann
