Garmin Forerunner 45/45S
Tech specs 
SizeSmall: 39.5 x 39.5 x 11.4 mm
Large: 42 x 42 x 11.4 mm
MaterialLens material: chemically strengthened glass
ChargingYes
BatteryLithium-ion
Battery lifeSmartwatch Mode: Up to 7 days
GPS mode: Up to 13 hours
Water-resistance5 ATM
WeightSmall: 32 g
Large: 36 g
SensorGPS/GLONASS/GALILEO, accelerometer, heart rate
Display208 pixel diameter; sunlight-visible, transflective memory-in-pixel (MIP)
Screen size1.04" (26.3 mm) diameter
ColorsIris, White, Black, Lava Red
OtherPLATFORM: Home Grown OS
PROCESSOR: Unknown
MEMORY: 200 hours of activity data
CONNECTIVITY: Bluetooth
Activity tracking 
StepsYes
DistanceYes
Calories burnedYes
ActivityYes
Floors
SleepYes
Heart rate24/7
Stress & recoveryYes
Pulse Ox
Respiration rate
UV exposure
Skin temperature
Galvanic skin response
Hydration level
Calorie intake
GPSGPS/GLONASS/GALILEO
Running featuresVO2 max estimate, cadence, GPS-based distance, time and pace, run workouts, foot-pod compatible
Swimming features
Other - VO2 Max
- Body Batter Energy Monitor
- Incident detection
Non-fitness functions 
Smartphone notificationsYes.
On-board music storage
Connected pay
LTE
Links 
Affiliate link*Amazon | Garmin
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