This item was found while cleaning out my parents' house. It is said to have the effect of increasing heat retention and relieving pain such as stiffness due to the effects of negative ions and far-infrared rays. I hope those who are suffering from knee or elbow pain will find it useful. The box says it's a set of two, but this is a single item for sale. Retail price: Set of 2 ¥4800 Approximate dimensions: Approximately 9cm x 23cm (The magnetic center section is 11cm wide) Although it is new, please understand that it has been stored at home for a long time. Please note that those who purchase immediately will be given priority, even if comments or inquiries are received. Returns and claims are not accepted. Thank you for your understanding. I work on weekends and holidays, so I may take a little time to respond to comments, but I appreciate your understanding. #Supporter #KneeSupporter #NegativeIonSupporter #Magnetic #HeatRetentionEffect