The Oura Ring 4 Charger is the only way to charge your Oura Ring. It’s fast, convenient, and easy. Your Oura Ring can take 20-80 minutes to fully charge on the Oura Charger, depending on its current battery level. It comes with a USB-C Oura Ring Cable cord, intended to be supplied by an external 5Vdc supply that complies with IEC 62368-1 standard. | Oura Ring 4 Charging Dock with UBC-C Cable - Size 4