【Please be sure to check the profile and only trade with those who agree!】 【Currently, I am not considering price reductions】 I am selling this because I am replacing it. I have used it for about a year, and currently the battery lasts for 4 days (5 or 6 days by default). New ones are expensive, so it's recommended for those who want to try it out. There is a scratch on the underside of the ring (see photo 2). It's on the sensor side (palm side), so it's not noticeable when worn, but it's still used, so please refrain from purchasing if you are concerned about other minor details. Please refer to the manufacturer's website for details. I cannot answer technical questions. Cancellations after shipping are also not accepted. Also, I am sorry, but please refrain from purchasing if you have zero ratings or only "bad" ratings. Thank you. 【If you have any questions, please be sure to ask before trading.】