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Polar M400 review: A feature-packed GPS running watch that can also track your steps and sleep - CNET
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Amazon.com: RuenTech Bands for Polar M400 / M430 watch Strap Replacement Soft Silicone Wristband Sports Band For Polar M400 and M430 Smart Sports Watch-Black L(5.5''-9.0'') : Electronics
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