＃39;Vinegar of oak tree&＃39; is a liquid of naturally cooled smoke, which is generated in the process of carbonizing oak trees. YLS is a material made from only effective components, which are extracted from this vinegar of oak tree.This YLS is a far-infrared radioactive material composed of over 200 organic materials useful to human body. It has an ability of SOD(super oxide dismutase), which removes alien substances from cells, normalizes circuits of cells and makes cells healthy. It is one of the best new materials developed in the 21st century, which is applicable to functional food products, health care products, body care products, and alternative medicines.