Displaying details for Fitbit Flex
 Fitbit Flex
Tech specs 
SizeSmall size fits wrists 14cm-16.5cm
Large size fits wrists 16.5cm-21cm
MaterialStainless steel casing, elastomer strap
ChargingUSB
BatteryLithium-polymer
Battery life5 days
Water-resistanceWater resistant up to 10 meters (1 ATM)
Weight10 grams
Sensor3-axis accelerometer, Vibration motor
DisplayFive white LED indicator lights
Screen sizeN/A
ColorsBlack, Slate, Tangerine, Teal, Navy, Violet, Blue, Lime, Pink, Red
Other
Activity tracking 
StepsYes
DistanceYes
CaloriesYes
ActivityYes
Floors
SleepYes
Heart rate
Vo2Max
UV exposure
Skin temperature
Galvanic skin response
GPS
Running features
Swimming features
Smartphone notifications
Other Auto sleep detection, silent wake alarm
Links 
View onAmazon
Amazon US rating3.7 out of 5 stars
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