The battery gives you several days of efficient use, so you don't have to charge too often. It has a built-in GPS, so you can see the distance of your bike ride.
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Apple Watch Ultra (GPS + Cellular, 49mm) Smart watch - Titanium Case with Yellow/Beige Trail Loop - S/M. Fitness Tracker, Precision GPS, Action Button, Extra-Long Battery Life, Brighter Retina Display
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