Contour Ceramic Massage Stones combine the indulgence of hot stone massage with the benefits of massage tools. Warm them up to soothe or cool them down to refresh with smooth, polished surfaces, they glide over skin, relieving tension as they go. Features: Award Winner Idea Award. Body safe. Double fired, biocompatible porcelain. Holds temperature can be warmed or cooled for extra stimulation. Ergonomic. Reduces strain on fingers and wrists. Durable. Non-porous and easy to clean Size 3.5 inches by 3.5 inches by 3.75 inches at its widest point.