Epson ProSense 307
Tech specs 
Size47.0 x 47.0 x 13.4 mm
MaterialLens Material:Plastic
Band:Quick-release Pro Silicone
ChargingUSB
BatteryLithium ion
Battery lifeGPS and HR: Up to 20 hours
GPS: Up to 24 hours
5 days activity tracking, 30 days Watch Mode
Water-resistance5 ATM (50m)
Weight49 grams
SensorGPS, integrated heart rate sensor, 3-axis accelerometer
DisplayEasyView display (Electronic Paper Display), reversible black-and-white, 240 x 240 pixels
Screen size1.1"
ColorsBlack, blue and white.
OtherPLATFORM: N/A
PROCESSOR: N/A
MEMORY: Up to the lesser of 248 workouts or 7,000 laps
CONNECTIVITY: Bluetooth
Activity tracking 
StepsYes
DistanceYes
Calories burnedYes
ActivityYes
Floors
SleepYes
Heart rateYes
Vo2MaxYes
Stress & recovery
UV exposure
Skin temperature
Galvanic skin response
Hydration level
Calorie intake
GPSYes
Running featuresBasic metrics: Distance, time, pace, speed, elevation change, calories.
Advanced metrics: Stride length, cadence, training effect, recovery, VO2 max, race time estimates
Training: Intervals, target pace, race mode, heart rate zones, metronome, customizable workout displays
Swimming featuresBasic Metrics: Lengths, distance, pace, stroke detection, SWOLF, stroke count, stroke rate, calories
Other - Time/date, alarm clock, stopwatch, music control
- Sport Modes: Walking, Treadmill, Triathlon, Indoor Bike
Non-fitness functions 
Smartphone notificationsYes
On-board music storage
Connected pay
Links 
Affiliate link*Amazon
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