The Ultrahuman Ring Air in matte grey, size 7, is a versatile activity tracker suitable for both indoor and outdoor use. powered by batteries with a battery life up to 6 days, this ring offers seamless tracking of your heart rate, calories, and distance travelled. Made of durable titanium material, it features advanced sensors such as infrared, accelerometer, and gyroscope to provide accurate data. With compatibility for iOS and Android operating systems, this ring also allows you to set goals, review data, and track your sleep patterns. The sleek black design and 2-year manufacturer warranty make it a stylish and reliable choice for fitness enthusiasts. Has marks as shown on pictures
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