【Product Name】OURA Ring Gen3 US6 Size Oura Ring 3rd Generation Heritage 【Color】 Silver 【Included Items】 Product box, cable, instruction manuals 【Condition】 I previously purchased this item, which had been barely used, and used it for about 1 year and 2 months. It paired normally, and measurements were accurate. The most recent time I fully charged it, it lasted for about 3 days and 5 hours. The battery life varies depending on usage, so please consider this as a reference. Since I wore it every day for measurements, there are scratches on the exterior. I did not use the included cable, and used my own type-C cable, so it is unused. Before listing, I have disinfected, cleaned, and initialized the device. Below, I have summarized the benefits of the ring using AI. Personally, it has been very helpful for health management, not only for sleep measurement, but also for improving my training based on my current cardiovascular age. (This is not a medical device) 【Product Details】 【Summary of Oura Ring Gen3 benefits by chat GPT pro】 Strong sleep analysis: Automatically estimates not only sleep time, but also sleep stages (deep/light/REM/wake). Makes sleep quality "visible" and easy to understand improvement points (Gen3's sleep algorithm has verification research comparing it to PSG). "Today's condition" is known through Readiness: Integrates sleep, heart rate, HRV (heart rate variability), etc., and scores fatigue/recovery. Oura's strength is that it's easy to use for judging training intensity and rest. 24/7 heart rate, HRV, and body temperature trends: Continuous measurement from daytime to sleep. It's easy to grasp "signs" of changes in physical condition through trends. Heart rate during exercise can also be measured: Can record heart rate during activities such as walking, combined with automatic activity detection. Suitable for continuous wear: Water-resistant (100m rating), ring-shaped and doesn't get in the way during sleep. 【Shipping】 ・We use anonymous shipping. ・We use recycled shopping bags and cardboard for packaging materials.