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Amazon.com: Fitbit Flex 2 Smart Fitness Activity Tracker, Slim Wearable Waterproof Swimming and Sleep Monitor, Wireless Bluetooth Pedometer Wristband for Android and iOS, Step Counter and Calorie Counter Watch : Sports &
Fitbit-measured steps and minutes of "fairly or very active" physical... | Download Scientific Diagram
![Amazon.com: Fitbit Flex 2 Smart Fitness Activity Tracker, Slim Wearable Waterproof Swimming and Sleep Monitor, Wireless Bluetooth Pedometer Wristband for Android and iOS, Step Counter and Calorie Counter Watch : Sports & Amazon.com: Fitbit Flex 2 Smart Fitness Activity Tracker, Slim Wearable Waterproof Swimming and Sleep Monitor, Wireless Bluetooth Pedometer Wristband for Android and iOS, Step Counter and Calorie Counter Watch : Sports &](https://m.media-amazon.com/images/I/41cN-mynhFL._AC_UF350,350_QL80_.jpg)