The eyes have it! The plant-based cooling phase change material cools to a comfortable 58 degrees and provides soothing relief for puffy eyes, swelling and cosmetic treatments. The Opal Eye Mask also relieves headaches and migraines and cools fevers. Refreshes to a cool state in the refrigerator after just 20 minutes. Stays cool approx. 30 to 45 minutes. Latex free. To clean, wash with mild soap and water then air dry.