Works as advertised
I made my wife very happy when I started including these stones as part of her massage therapy. The metal case is a bit thin, but it does heat the stones in about 30 minutes, and they stay hot for some time.  Note, the stones are quite hot - they are very uncomfortable if placed on the bare skin. I suggest placing a bed sheet between the hot stone and the skin. My only complaint is that the thin felt-like material on the inside of the case seems cheap; otherwise, the stone kit works as advertised.
Rating: 4 stars