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Polar M400 Activity Tracker/GPS Running Watch With Heart Rate Sensor! | Gadget Explained - Reviews Gadgets Electronics Tech
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Polar M400 review: A feature-packed GPS running watch that can also track your steps and sleep - CNET
Polar - Hey Polar M400 iOS users! Smart notifications have arrived! Keep up-to-date wherever you want, with notifications about incoming calls and messages sent straight to your wrist! How to activate smart
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