New in box, ring not included The Oura Ring 4 Charger is the only way to charge your Oura Ring 4. Your Oura Ring 4 typically charges fully in 20-80 minutes, depending on its current battery level. It’s fast, convenient, and easy. It comes with a USB-C to USB-C Oura Ring Cable cord, intended to be supplied by an external 5Vdc supply that complies with IEC 62368-1 standard.