Polar A370
Tech specs 
SizeThickness: 13.5 mm
Width: 23.5 mm
MaterialSoft Silicone or Polyurethane (TPU) wristband
ChargingMicro USB
Battery110 mAh Lithium-polymer battery
Battery lifeUp to 12 hours of training with mobile GPS
4 days of activity tracking with continuous heart rate and 1 h of training per day
Weight31.7g (S), 37.3g (M/L)
Sensor3d-accelerometer, heart rate monitor
DisplayWide-viewing angle full color TFT display with capacitive touchscreen
Screen resolution 80 x 160 pixels (RGB)
Screen size13mm x 27mm
ColorsAvailable in 6 colors.
Activity tracking 
Calories burnedYes
Heart rateYes
Stress & recovery
Pulse Ox
Respiration rate
UV exposure
Skin temperature
Galvanic skin response
Hydration level
Calorie intake
GPStaps into the GPS on your phone
Running features
Swimming features
Other Inactivity alert, Vibration alerts, Alarm, Sport profiles
Non-fitness functions 
Smartphone notificationsYes
On-board music storage
Connected pay
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