you can see here sort of: https://www.rainshower.com/new/relax.html
They also sell on amazon com USA
I have two balls and two replacement Bags that I brought from the USA.
Yes, there is chlorine in the water here. But I now live in a Japanese style house with a tub that doesn't really fit me (I'm 5'10")
So I am not taking a bath every night any more.
About 1x every 2 week I go to the public bath house. These balls or just pull the pouch through the water twice (swish swish) is enough, squeeze out the excess water and hang on a hook until the next bath.
You can use one bag over and over many times (3 years and more?)
You can read reviews here on amazon
Anyway, my daughter still takes baths so we still have our first original bag. And have never opened the replacement bags.
Selling each bag for 2000yen. You can have the plastic "cage" ball too, but it's not really neccessary.