Hot Stone Set 8pcUses of Hot Stone Set 8pc This a set of 8 pieces of Basalt Stones in three sizes small, medium and large. These sets are ideal if you need to add more stones to an existing set or if you want to build your own custom set. More Hot and Cold Stone Therapy Each set contains 8 stones of the selected size. Approximate stone sizes Small size stone 5 x 6. 35cm (2 2 1 2") Medium size stone 7. 62 x 9cm (3 3 1 2") Large size stone 9. 5 x 10cm (3 3 4 4")