The Two Stone Shoulder/Lower Back device are two large smooth stones, hand selected and matched, joined by two stiff, yet flexible members. This unique, patented design by Fred Harrison of Stonehenge, demonstrates the flexibility and stiffness of these items enabling it to be shaped to cup over your shoulder, just exactly where you need it. This system also works well for arms, legs, and lower backs. Instructions: Soak the device in hot tap water, or water warmed through other means. Test the heated moist stones by touch the stone to the inside of your wrist. Let cool if too hot. Place the device where it is needed. Relax and let the heat and pressure help work the kinks out.