Oura Oura Ring 4

An Oura Ring 4. Size 7. Silver. Excellent functioning capability. Hairline scratches throughout. Box, user guide, charging dock station, charging cable included! Tech Specifications Sensors Red and infrared LEDs measure blood oxygen levels Green and infrared LEDs alternate to measure heart rate and heart rate variability 24/7 and respiration rate Digital sensor measures temperature trends Accelerometer tracks movement and activity 24/7 Compatibility Oura App is available in English, Finnish, Japanese, German, French, Spanish, Italian, Norwegian, Swedish, Czech, Dutch, and Danish Supports metric and imperial units of measurement Integrates with 40+ apps Available on iOS and Android Weight and Dimensions Width: 7.90mm Thickness: 2.88mm Weight: 3.3 to 5.2 grams (depending on Oura Ring size) Battery Life 5-8 days of battery life* Typically charges in 20-80 minutes, depending on battery level Quality Materials Non-allergenic titanium on inner & outer surfaces Seamless titanium interior Water resistant up to 100m/328 ft Minor scratches from regular wear are normal Connectivity Bluetooth Low Energy Automatic firmware updates via Oura App EMF-safe Supports airplane mode FCC-certified