I have a ICD in my body. ICD is an abbreviation of "Implantable Cardioverter Defibrillator". I have a disease of my heart. It is not a so severe disease, but I have it for a rainy day. It has some advantage in public welfare, but it has some disadvantage such as the limit of the exercise and the　operation for exchange. I don’t usually mind it very much but I'll hate it when the day of the operation approaches. I want someone to invent ICD which does not use a battery. Thank you for reading my note! :)