Oura Ring 4, perfect for health management, silver, size 9, Bluetooth compatible. - Model Name: Oura Ring 4 - Color: Silver - Size: 9 - Bluetooth: Yes Thank you for viewing. This is a brand new, unopened Oura Ring, 4th generation. Size: US 9 Color: Silver Retail Price: 52,800 yen ■ Product Description By wearing the Oura Ring 24/7, you can measure health metrics and receive insights. It accurately reads over 30 biometric signals directly from your finger, which directly impact your health.