It relieves tired eyes and is suitable for use before sleep or in relaxation Principle: when the air and moisture through the eye mask, contacting the iron powder heater that contained in the mask, they will be heated and become steam. Iron powder, Activated Carbon, Vermiculite, Super Absorbent polymer, Sodium chloride, Water How to use: 1) Remove eye mask from pouch 2) Tear along perforation, then place ear straps around ears 3) Place white-colored side of mask on eyes. Heat will last for approximately 10 to 15 min. Do not use if: 1) you have ailment or inflammation on eyes. 2) you have scars, swelling, or eczema on or around eyes.