The power of heart rate in their slimmest design yet. The Altra is packed with powerful and essential features such as tracking steps, calories and distance, auto sleep tracking and sleep stages, a battery life of up to seven days, clock and tap display. And on top of that it boasts PurePulse Heart Rate, SmartTrack, auto exercise recognition; call, text and calendar alerts, interchangeable bands and reminders to move. www.fitbit.com
