Oura Ring Gen 4 Size 9 Silver Color Weight and Dimensions Width: 7.90mm Thickness: 2.88mm (similar to a wedding band) 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 Track over 50 health and wellness metrics, and get personalized insights into your sleep, activity, stress, metabolic, heart health, and women’s health. With innovative, AI-powered tools like Oura Advisor, get exclusive access to actionable insights that become increasingly tailored over time. What's Included: Oura Ring 4 Size-specific charger USB-C cable New in sealed box.