This medical stone roller is made of natural medical stone/, it is a natural silicate mineral, is a biologically active composite mineral. Medical stone emits mineral elements such as calcium and iron, which can increase the mineral and nutritional properties of food. And medical stone has the effect of regulating the PH value, which can effectively regulate the acidity and alkalinity of food and make food more healthy. You can use it to grind herbs, foods, spices, grains, etc. It is simple to use, just repeatedly crush the food. The food ground by it is more natural and healthy, and original taste and flavour. Length: 15.7 in/40cm, Width 3.9 in/10cm, Height 3.9 in/10cm. Net Weight: 24 lb.