Vanta Smart Ring™

What the Vanta Smart Ring tracks: Heart rate, blood pressure, blood oxygen (SpO2), sleep stages, steps, calories, and stress levels — continuously, all day and night. Compatible with: iOS 8.0+ and Android 5.1+. Free app download included. Battery: 5 to 7 days per charge. Charges fully in 1 to 2 hours. Waterproof rating: IP68 / 3ATM. Safe for swimming and showering. Material: Stainless steel. Hypoallergenic. Sizes available: 7 through 12. If between sizes, size up. Subscription fees: None. Ever.