These Soothing pattern Eye Pillows are filled with your Lavender flowers, Rice and Flaxseed. For Heat Therapy - You can heat these hot/cold aromatherapy eye pillows in the microwave for 30 seconds to heat them up, then repeat for 15-second increments until you have reached the desired warmth. For Cold Therapy - To cool your eye pillow put it in a Ziploc bag in the freezer for at least one hour to have a cold pack or keep one to store in the freezer to use as needed!