Polar M400: Running and activity tracking in one (pictures) - CNET

Polar's newest GPS heart rate smartwatch lasts for 40 hours - CNET

Polar M400: Running and activity tracking in one (pictures) - CNET

Polar M400 - with heart rate sensor - GPS watch

Polar M400 - With heart rate sensor - GPS watch - cycle, running

Time to look at smartwatches and fitness trackers for school - CNET

Garmin Vivoactive review: Garmin's first fitness smartwatch misses the mark - CNET

Polar M400 - with heart rate sensor - GPS watch

Polar M400 - With heart rate sensor - GPS watch - cycle, running

Garmin Vivoactive review: Garmin's first fitness smartwatch misses the mark - CNET

Polar M400: Running and activity tracking in one (pictures) - CNET

Polar M400: An activity tracker with the heart of a GPS running watch - Video - CNET

Review: Polar M400 Fitness Tracker Watch

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