Deflecto Reusable Cool and Heat Cap provides targeted pain relief for headaches and migraines while helping to reduce temperature. The cap gives immediate comfort from heat, tension or fatigue whilst its dual comfort technology gives you the option of transitioning between hot and cold cycles. To use, let the pad cool completely after heating. Placing a hot pad directly into the freezer can damage the material and reduce product life. To prevent moisture buildup or freezer burn, place in a ziplock or freezer-safe bag. Freeze or refrigerate for at least two hours, or overnight for best results.