Unlike typical heart rate monitors that require uncomfortable chest straps, this heart rate device is as unobtrusive as a standard wrist watch and provides an EKG accurate reading to 1 beat-per-minute at a touch of a button. A signal beeps twice when your heart rate exceeds or falls below your optimal beats-per-minute target zone, informing you when to increase or decrease workout rate. Chronograph and countdown timer features allow you to set time benchmarks, and the calorie counter calculates caloric energy output based on your heart rate. Includes calendar, hourly chime, alarm, and current time features, displayed on any easy-to-read backlit LCD. Battery included.