We recommend microwaving it on medium-high heat for 30 seconds. However, microwave wattages may vary so you can microwave your Manta STEAM Mask for 5 more seconds to increase the warmth. But don’t microwave for more than 40 seconds as this could cause injury to the user or damage the mask. If your microwave doesn’t have a rotating tray, start with 15 seconds. Remove the eye cups, flip them over, then continue microwaving for 15 seconds. If you live in a dry climate, sprinkle a few drops of water on the eye cups before heating them.