Oura Ring Gen 4, Black, size 9 - Smart activity tracker with temperature sensor, heart rate monitor, and sleep tracker - Ideal for running and jogging - Improved accuracy, personalization, and battery life: lasts 5-8 days on a charge - Features Smart Sensing technology and a fully-titanium design - Comfortable to wear all day - Members can track over 50 health metrics: sleep, activity, stress, metabolism, heart health, and womens health. AI tools like Oura Advisor provide personalized insights - Non-members receive Readiness, Activity, and Sleep data