The patch contains a high percentage of water which works with the bodies natural cooling system helping to cool the body. As the temperature rises the heat of the skin causes the evaporation of water contained within cooling gel sheet which creates a cooling sensation on the surface of the skin. The excellent heat transfer ability is made possible by the gels unique structure which disperses heat freely and maintains a constant and steady cooling effect that lasts up to 8 hours. Size:5*12cm Package:1pcs/aluminum foil bag; 4 aluminum foil bags /middle box, 200 middle box/carton.