A self-heating, on-the-go eye mask from Popmask designed to start warming within 30 seconds to provide soothing relief to tired eyes. Perfect for resting, meditating, or for whenever you need a little extra relief. Made from non-woven cotton, each heat cell contains iron powder, vermiculite, activated carbon, salt, and water - all naturally occurring ingredients. * Contains 5 self-heating eye masks * Ear loops provide a secure fit * Heat lasts 20 minutes * Fragrance-free **How to Use:** When the pouch is opened, the iron powder inside heat cells reacts with oxygen in the air causing it to heat up gently. The mask reaches a maximum temperature of 100.4 F° or 38 C° and stays at the temperature for at least 20 minutes.