Purchased two years ago, but used for only one season. I didn't use it last year. It shows signs of use, but there is no damage to the heating element. When using, please confirm the official instructions for "Range de Yutapon" before use. ● Simply heat it in the microwave for a comfortable warmth that thoroughly warms cold feet. ● It's a soft and comfortable gel-type hot water bottle. ● The warmth lasts for about 7 hours. (This is a guideline when used inside a futon. The duration may vary depending on room temperature and usage environment.) ● Comes with a washable, fluffy, dedicated cover. ● Can be used repeatedly. 【Uses】 ● Warming during sleep Ingredients ● Water ● Gelling agent ● Coloring agent 【Cover Material】 Polyester