This is for the back and waist, using four balls. Simply lie on your back on this device and apply your weight, and the ball heads will work like an anma massage and acupressure. Your posture, which tends to be bent forward daily, will be stretched backward with this device, leaving you feeling refreshed. A whole-body pressure health device you can use by yourself. Easy to use, without electricity or medicine. This single device can substitute for anma massage and acupressure. Because you apply pressure using only your own body, there's no need for electricity, medicine, or even someone else's hands. (The above is from the official website) - It feels really good! (Personal impression) - Adjustable height function - There are some minor scratches, stains, and fading from use. - Minimal packaging to keep the price down. Massager