Sensors & Components
Battery and Power
We recommend charging your Fitbit Flex 2 every few days to ensure that you're always tracking.
Battery life up to 5 days. Battery life and charge cycles vary with use, settings, and other factors; actual results will vary.
Battery type: Lithium-polymer
Charge time: One to two hours
Radio transceiver: Bluetooth 4.0
Click Here for more detailed specifications.