- Oura Ring 4 smart ring. The future of wearable technology with this sleek gold and silver ring. - Sized 12, - Perfect for tracking your health &staying connected on the go. - Accuracy - Smart Sensing, Oura tracks over 50 health metrics, including sleep, activity, stress, heart health, and women’s health metrics. - Oura Ring 4 is powered by Smart Sensing, which adapts to your unique finger and activity, delivering accurate, continuous data, day and night. - Battery With up to 8 days* of battery life. Oura Ring 4 Accuracy - Smart Sensing Oura tracks over 50 health metrics, including sleep, activity, stress, heart health, and women’s health metrics. Oura Ring 4 is powered by Smart Sensing, which adapts to your unique finger and activity — delivering accurate, continuous data, day and night. - Designed For 24/7 Wear. The updated design of Oura Ring 4 is more comfortable, fits better than ever, and is water resistant. The first all-titanium smart ring. - Sleep - Oura provides insights into your sleep staging throughout the night, blood oxygen levels, HRV and nighttime heart rate. - Readiness - Oura Readiness Score. Takes into consideration over 50 different health metrics — temperature, heart rate, HRV, and sleep. - Activity - Whether you're running a marathon or running errands, Oura tracks your daily activity, steps, calories burned and workouts. - Heart Health. From monitoring your daily heart rate and HRV to discovering your Cardiovascular Age and Cardio Capacity.