1. Trace Mineral Grains: The 360��rotation of grains can instantly remove the dead skin on your feet.2. Removable Roller: The micro particles on the surface of the roller can massage your feet comfortably. Besides， the grains can be replaced and cleaned at any time.3. More Sanitary: The roller is waterproof. It is easy to clean. Thus it is more sanitary.4. Curve Roller: It is simple to operate. No extra technique needed.5. Ergonomic Design: The using of it will not take much energy. Besides， you can take it to anywhere for its size is small.6. Power Supply with 2 Batteries: Two AA batteries makes the graining easier and more simple.Notice: The batteries are not included. You need to buy them.