Withings ScanWatch
Tech specs 
Size38mm: 38.4 x 13.2mm; 18mm watch strap, fits wrists from 146-211mm
42mm: 42 x 13.7mm; 20mm watch strap, fits wrists from 163-239mm
MaterialWatch face: Sapphire glass
Case: Stainless steel
Band: Silicone (38mm) or FKM (42mm)
ChargingUSB
BatteryLithium Ion
Battery lifeUp to 30 days in normal use. +20 additional days in power reserve mode (time and activity tracking only)
Charging: ~2 hours to 100%, ~1 hour to 80%
Water-resistanceUp to 50 m (5 ATM)
Weight38mm: 58g
42mm: 83g
SensorExclusive multi-wavelength PPG heart rate/SpO2 sensor, Stainless steel electrodes, High precision MEMS 3-axis accelerometer
DisplayPhysical hour and minute hands
Daily activity subdial
Screen size13.8mm PMOLED
ColorsMultiple
Other
Activity tracking 
StepsYes
DistanceYes
Calories burnedYes
ActivityYes
FloorsYes
SleepYes
Heart rateYes (high or low heart rate alerts, irregular heart beat)
Stress & recovery
Pulse OxYes
Respiration rateBreathing disturbances detection via oxygen saturation
UV exposure
Skin temperature
Galvanic skin response
Hydration level
Calorie intake
GPSConnected GPS
Running features
Swimming features
Other Instant ECG on demand
Delivers heart health notifications when heart rate is atypical (too low or high) and if irregular rhythms are detected.
Monitors oxygen saturation during the night and identifies Apneic episodes
Non-fitness functions 
Smartphone notificationsYes
On-board music storage
Connected pay
LTE
Links 
Affiliate link*Withings
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