Polar Running HeartRate Monitor Watch Stopwatch RS100
The RS100 is a simple, no-fuss solution that’s perfect for entry level runners who want to get on the right track to fitness. It comes with a variety of uncomplicated yet highly effective features. 
-Measures your heart rate combined with flexible timing features 
-Automatically sets your heart rate aerobic zones depending on how hard you want to train 
-Shows you how many calories and the percentage of fat you’ve burned 
-Calculate your time spent on each exercise, how well you’ve kept to certain sport zones and how many calories you’ve burned 
-Records up to 99 lap/splits for every training session so you can work to improve on your best time and monitor your heart rate over time
Basic features
    Automatic/Manual target zone (% / bpm / HRR%)
    Backlight
    Easy start (setting wizard)
    Heart rate (displayed as % of maximum heart rate)
    Heart rate (displayed as bpm)
    HeartTouch™, button-free operation of wrist unit
    KeyLock
    Over-sized display
    User configurable displays - top line
    Visual and audible alarm in target zones
    Water resistant - 50m 
Computer connectivity
    Edit wrist unit settings with Polar UpLink Tool and transfer them to your Polar product (UpLink)
    Transfer logos from Polar web site to wrist unit (UpLink)
Cycling features
    Bike mount - opt.
Data transfer
    UpLink (PC with a sound card and headphones/dynamic loudspeakers required)
Polar exercise features
    Average heart rate of each lap
    Average heart rate of total exercise
    Exercise Date
    Exercise Set (extended exercise profiles)
    HR-based target zones with audible alarm - 1
    HR-based target zones with visual alarm - 1
    HRmax (age-based)
    Maximum heart rate of total exercise
    Polar OwnCal® 
    Polar OwnCode® (5kHz)
    Polar OwnZone®
    Wireless ECG accurate heart rate
Recording features
    Average heart rate
    Calorie expenditure - exe.tot.fat%
    Exercise Time (total)
    Exercise file info page with date and time
    Lap info
    Number of exercise files (with summaries) - 1
    Target zone limits
    Time in target zone
Transmitter belt
    Polar T31 coded™ transmitter
    Polar WearLink® 31 coded transmitter (changeable battery) - compatible 
Watch features
    Alarm with snooze
    Date and weekday indicator
    Low battery indicator
    StopWatch
    Time of day (12/24h) with alarm