Zechsal magnesium oil is the most concentrated liquid form of magnesium chloride, dissolved in water. It’s called magnesium oil because it is greasy to the touch. Magnesium oil is ideal for quick and effective magnesium absorption through the skin. It’s practical in use and benefits the whole body. The best areas for magnesium absorption are the feet, the underarms and the belly region. However, if you have problems with cramp or tense muscles, it would be a good idea to treat the affected area itself.