Tech specs 
SizeSmall size fits wrists 14cm-16.5cm
Large size fits wrists 16.5cm-19.5cm
X-large size fits wrists 19.5cm-22.6cm
MaterialStainless steel casing, elastomer strap
ChargingUSB
BatteryLithium-polymer
Battery life7-10 days
Water-resistanceWater resistant up to 10 metres (1 ATM)
Weight26 grams
Sensor3-axis accelerometer, Altimeter, Vibration motor
DisplayOLED
Screen sizeN/A
ColorsSlate, Blue, Burgandy, Black
Other
Activity tracking
Steps 
DistanceYes
CaloriesYes
ActivityYes
FloorsYes
SleepYes
Heart rateYes
Vo2Max
Stress & recovery
UV exposure
Skin temperature
Galvanic skin response
GPS
Running features
Swimming features
Smartphone notifications
Other
Links
Affiliate link*Caller ID
Read moreClock, auto sleep detection, silent wake alarm
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**Manufacturers may update tech specs of their devices over time. While we cannot guarantee that the information on Gadgets & Wearables tech specs pages is 100% correct, we promise to review this content regularly and do our best to bring you the most precise information. To be absolutely sure of tech specs of a particular device, we recommend checking the manufacturer’s website.