This picture of darkness is in place of the ball because my cat played with it once and it vanished into the ether. It's been over a week. I don't think it will return.
The ball is as designed but it's not worth the cost when it is so easily lost. The charging door is also very insecure and comes off too easily. The charging port is too loose so the ball has to be at a precise angle to charge.
As it works my rating is positive but I don't think you should buy it. Get the cheap puff balls with the launcher instead. My cat preferred that to the ball and those are a dollar for 50 at the dollar store so replacement is easy.