Tech4o Men's Pro Trainer Sport Fitness - Watch The Pro Trainer has user customizable screens with large easy to read 33mm display Measures speed and distance and calculates calorie burn Heart Rate monitoring with zone alerts Logbook with 10 day memory,dual time date and day,two daily or weekly alarms and a countdown timer Maintains a backlight and water resistance:100M Wrist device designed for fitness enthusiasts who have taken fitness program to the next level and want accurate, coded heart rate monitoring with speed and distance stats 33-millimeter easy-view module makes it easy to check progress during exercise Accelerometer sensor detects changes in user's movement that are translated into varying degrees of electric current within the sensor 2.4GHz wireless transmission is coded to prevents interference from other devices; electroluminescent backlight; water resistant to 100 meters Includes limited one-year manufacturer's warranty