soothing and relaxing [SEP] these rocks have helped me so much i have a chronic hip and back problem and arthritis as well i have been hobbling around for weeks even after physical therapy i used these once and was percent better after the first usage they are beautifully presented in the clam shell they get hot enough after to mins they stay warm for about to mins which is a bit of a disappointment but they warm fast if you want longer treatment or to just leave them on your body until they cool very soothing