We prefer to avoid reviewing an item that we haven't actually owned, but when we read about a product called the Chin-Chiller, we couldn't resist.
The description of the chin-chiller indicates that it remains cooler than the ambient temperature and thus provides a way to keep your chinchilla cool. This is bogus! How can something without external power remain cooler than the air temperature around it?
What is more likely is that the material that these Chin-Chillers are made of is a good conductor. As such, it feels like it is cooler to the touch because it conducts the heat from whatever touches it. But if the air is warmer than the chinchilla then the Chin-Chiller isn't going to have any effect.
This product is akin to a fan. When a fan blows air on your face you feel cooler. But the air isn't any cooler because it is being blown around by a fan. At best you're feeling cooler because the moving air is pushing away the air close to your face that you've warmed up and replacing it with slightly cooler air in the room.