A perennial favourite, OPAL s cooling eye masks are a must ! They are ideal for headaches and hangovers and for unfortunate hayfever sufferers they soothe and cool puffy, itching eyes. The soft touch eye mask can be used warm or cool - just adjust the temperature by plunging the mask into a bowl of cold water to chill, or warm ( not boiling) water to warm. Generally the eyemask is best used just as it comes, at room temperature... Water naturally absorbs heat, so the distilled water fill will gently cool and relax the sensitive skin around the eye. This area is very tender and should not be subject to extreme temperatures.