The Garmin Forerunner 255 Music is a lightweight comfortable GPS running smartwatch that gives overview of your sleep HRV status and daily workout with morning report. The watch uses wrist-based heart rate sensor to offer performance monitoring features including evaluating current training status. The Forerunner 255 gets you ready for your next race with training tips personalized daily suggested workouts and completion time predictions based on course details weather and performance. Utilize a full suite of advanced metrics and training tools to reach your goals.The Forerunner 255 Music Tune your Training by adding a beat to your step plus music to motivate you along the way. You can Download up to 500 songs plus playlists from your Spotify Deezer or Amazon Music accounts (subscription required). It helps create your own custom workouts on Garmin Connect online fitness community. The watch constantly samples your heart rate2 with our latest-generation heart rate sensor and will alert you if it stays too high or too low while you’re at rest. It also helps gauge how hard you work during activities — even while swimming. The Forerunner 255 Music provides a long battery life up to 14 days in smartwatch mode and up to 30 hours in GPS mode. With Forerunner 255 you can receive smart notifications track your runs with the LiveTrack feature and customize with free watch faces apps and more from Connect IQ store.