Structure ultraLightweight 20.3g, high elasticity with skin-friendly braided belt for incredible comfort. Wrist belt less intrusive than a heart rate belt when exercising. Accurate, dynamic heart rate, real-time heart rate data for each exercise. Several exercise modes, indoor, outdoor, aerobic or anaerobic. Charging time 1h30 Maximum use time 65h magnetic charging Waterproof IPX7 Accuracy to within 1 pulse compared with a heart rate belt. 5 led colors for heart rate interval 50-60% indicator flashes blue interval 60-70% indicator flashes green interval 70-80% indicator flashes yellow interval 80-90% indicator flashes orange interval 90-100% indicator flashes red
