The Forerunner 405CX is the evolution of GPS-enabled training. This sleek sport swatch tracks your time, distance, pace and heart rate, then wirelessly sends the data to your PC for later analysis. The 405CX features heart rate-based calorie computation.Loaded with serious training features, Forerunner 405CX continuously records your time, distance, pace, calories burned and heart rate. Each workout is stored in large internal memory so you can review and analyze the data to see how youve improved. And advanced training features will challenge you to step up your pace - race against Forerunner's Virtual Partner to improve your times, or set up interval workouts without having to circle the track. You can even download recorded courses to compete against previous workouts. To use the watch, simply tap the touch bezel to change screens without fumbling for a button.Forerunner 405CX comes with a flexible, wireless heart rate monitor to help you make the most out of your training. The digital heart rate monitor continuously tracks heart beats per minute and uses your heart rate for advanced calorie computation, so you know how many calories you're burning. Train in a certain heart rate zone to improve your fitness level or compare your pace and heart rate to past performance on the same run.