Flex uses five white LED indicator lights to show you how your day is stacking up against your goals. Each light represents 20% of your goal. Just tap the display twice to see your progress against your daily goal.
|SMALL*||5.5 - 6.9 inches (140 - 176 mm)|
|LARGE*||6.3 - 8.2 inches (161 - 209 mm)|
|WIDTH||0.6 inches (13.99 mm)|
Fitbit's trackers are the first all day activity trackers to offer Bluetooth Low Energy connectivity, so you see your stats in real-time.
Syncing occurs automatically any time Flex is within about 20 feet of the wireless sync dongle and is relatively motionless. The dongle plugs into your Mac or PC's USB port. Syncing and uploading require use of the Fitbit Connect application.
Syncing Flex™ to your smartphone or tablet requires Bluetooth Low Energy. This allows your Flex to sync wirelessly and automatically with a wide range of leading iOS and Android Smartphones.
For a full list of supported devices, visit: https://www.fitbit.com/devices
If your phone does not support Bluetooth Low Energy, you're still in luck. The Fitbit mobile app works with all smartphones for logging data, receiving notifications, and viewing graphs and charts based on your last sync.
We recommend syncing your data regularly. As long as Flex has battery power, it tracks the most recent seven days of detailed, minute-by-minute data. It also tracks your daily total for the past 30 days and summarizes your daily calories, distance, and steps taken.
Flex battery lasts approximately five days when fully charged. When charging your Flex the LED lights will indicate its level of charge. All 5 lights will light up when it's fully charged. You can also see your battery level on your Dashboard and mobile application. Remember to charge your Flex every 3 to 5 days to ensure you are always tracking.
|BATTERY LIFE||5 days|
(FOR WIRELESS SYNC)
|Bluetooth Low Energy|
|PC BROWSERS||MAC BROWSERS|
|chrome||12 and up||12 and up|
|firefox||3.6.18 and up||3.6.18 and up|
|internet explorer||8 and up||---|
|safari||---||5.0.5 and up|
Flex uses a MEMS 3-axis accelerometer that measures your motion patterns to determine your calories burned, distance traveled, steps taken, and sleep quality. Flex also contains a vibration motor, which allows it to vibrate when alarms are set to go off.
Flex™ is water resistant. It should be able to brave all the elements of your everyday life.
|OPERATING TEMPERATURE||-4° to 113° F
(-20° to 45° C)
|NON-OPERATING TEMPERATURE||-22° to 140° F
(-30° to 60° C)
|WATER RESISTANT||Device is water resistant, and can be submerged up to 10 meters.|
|MAXIMUM OPERATING ALTITUDE||30,000 feet (9,144 m)|
Fitbit Flex comes in multiple color options.
Additional colors available as accessory bands.