Fitbit Charge HR
Tech specs 
SizeWidth: 21mm
Small: 13.7cm-15.7 cm in circumference
Large: 15.7cm-19.3 cm in circumference
XL: 19.3cm-22.1 cm in circumference
MaterialStainless steel casing, elastomer strap
ChargingUSB
BatteryLithium-polymer
Battery lifeup to 5 days
Water-resistanceSweat, rain and splash proof.
Weight26 grams
SensorOptical heart rate tracker, 3-axis accelerometer, altimeter, vibration motor
DisplayOLED
Screen size0.9 cm
ColorsPlum, Blue, Tangerine, Black
Other
Activity tracking 
StepsYes
DistanceYes
CaloriesYes
ActivityYes
FloorsYes
SleepYes
Heart rate24/7
Vo2Max
Stress & recovery
UV exposure
Skin temperature
Galvanic skin response
GPS
Running features
Swimming features
Smartphone notificationsCaller ID
Other Clock,auto sleep detection, silent wake alarm,auto exercise recognition
Links 
Affiliate link*Amazon | Fitbit
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