Delivers in 2-3 business days to US customers. Accent your style while enhancing your fitness with the vivosmart 4 activity tracker. This slim, smart wristband is loaded with features to track your daily activity and your sleep stages all night. Wrist-based heart rate and Pulse Ox sensors help you learn more about your body, with all-day stress tracking, Body Battery: energy monitoring, VO2 max and more. Smart notifications keep you connected when paired with a compatible device, and up to 7 days of battery life will keep you going strong. Black, midnight, S/M.