WEGO Pace & Heart Rate Monitor With Easy to Use - Efficient Sensor for Extended Battery Life and Power Management Optical heart RATE technology - no chest strap required Easy to Use - efficient sensor for extended battery life and power management 3 Operation modes - time, chronograph and heart RATE. Heart RATE zone, percent of max heart RATE Custom user profile, 2 daily alarms, 12/24 time, dual time zone and date. There is a second chrono with a working range of up to 24 hours