... four massage balls in it can walk up and down, mute design.3. A great of ... massage ,hammer shock and more other massage technique ,performed on the head, neck, back, waist and other parts . It ... fatigue.4. The button of kneading and walk, if you click on it, it will do full-back, ... kinds: strong, medium and weak6. The seat cushion has three massage features: sustained, tap, staggered, which can ...