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Smart ring Ultrahuman Ring AIR – sleep and fitness tracker, Titanium, Size 5, PPG SpO2, USB-C, 6 days battery
Summary description:
Ultrahuman Ring AIR is a smart ring activity tracker in a round titanium form factor (Size 5) designed for sleep and fitness monitoring. It uses infrared photoplethysmography (PPG) to measure blood oxygen and heart-rate related metrics, connects via USB‑C, and features a 24 mAh LiPo battery with up to 6 days runtime. Narrow 8.1 mm profile for continuous wear; standard app features have no fee.