Meet the all-new Fitbit Flex 2-a slim, swim-proof fitness wristband that's ready to go wherever life takes you. The ultra-thin, removable tracker hides in bands, bangles and pendants, so you can wear it in a way that's all your own. Automatic all-day activity and sleep tracking show you how your entire day addsup, and SmartTrackautomatic exercise recognition records your exercises for you. The discreet progress display uses color-coded LED lights to keep you connected to calls, texts and Reminders to Move. Plus you don't have to worry about getting it wet-whether you're swimming in the pool or running in the rain. It's the next generation model of our most iconic tracker. No fuss, all fun, and fit for every you. Using Bluetooth LE wireless technology, Fitbit Flex 2 sends smartphone notifications and syncs automatically to computers and 200+ mobile devices. Smartphone notifications may require Android 5.0+. Syncing range: Up to 30 feet Syncing requires Bluetooth LE and Internet connection. Windows 10 computers that do not have Bluetooth LE will need a wireless sync dongle in order to sync. Syncs with Mac OS X 10.6 and up, iPhone 4S and later, iPad 3 gen. and later, Android 4.4 and later, and Windows 10 devices.. The Fitbit Flex 2 wristband is made of a flexible, durable elastomer material similar to that used in many sports watches. Flex 2 also has a surgical-grade stainless steel clasp.