POLAR Unite Waterproof Fitness Watch (Includes Wrist-based Heart Rate and Sleep Tracking)

Lightweight fitness tracking smartwatch to help keep you active
Up to 50 hours of battery life on a single charge in training mode (up to 4 days in watch mode)
Easy, single button use
Features advanced, wrist-based heart rate monitoring and specialized sleep and recovery tools for improved performance
Water resistant with GPS that tracks every step and turn