This is a radium hot spring device from Onmori Honpo. I purchased it in 2021 because a family member was ill. I used it for about six months. The color of the ore is different from that on the Onmori Honpo website and pamphlets, but this is not due to discoloration; it was like this from the beginning. The size is also slightly smaller. I confirmed with the official website, and it seems there are individual differences and variations in specifications. After use, I wash it thoroughly with a brush and then dry it. When you put it in the bath, it warms the body very well. Even if you're not sick, it seemed good for winter and cold sensitivity. Please consider the above condition before purchasing.