Track your steps, distance, calories burned, active minutes, hourly activity and stationary time. Automatically track activities like running, sports and aerobic workouts, then see exercise summaries in the Fitbit app. When you get calls and texts, Flex 2 vibrates and the discreet LED display flashes colour-coded lights. Fitbit flex 2 is the first swim-proof device from fitbit, meaning it is water resistant to 50 meters. With up to 5-day battery life; in an ultra-slim package, you can track all day and night without needing a charge. Size H20.2, W3.3, D10cm. Weight 17g.