Beurer PM15 Heart Rate Monitor Watch operates without needing a chest strap, allows you to monitor your heart rate and set a training zone with upper and lower limits according to your training objective. The heart beat is measured and displayed with ECG precision, without your having to wear a cumbersome chest strap. All you need do is at-tach the monitor to your wrist and touch the sensor on the face of the monitor with your finger or thumb. Your heart beat can be determined within seconds with ECG precision by finger sensor measurement on the arm, upper part of the body or other arm in relation to a sensor on the back of the heart rate monitor. This heart rate monitor is thus particularly suitable for persons who cannot or do not wish to wear a chest strap as well as for sports such as hiking or walking. Other features of this heart rate monitor include a time function, stopwatch, wake alarm and countdown timer. Of course, diagnosing the cause of heart palpitations is not always easy and sometimes requires close and long-term cooperation of the patient and the medical staff. For this reason, most people who suffer from heart palpitations are advised to use the heart rate monitor during their daily activities. When the heart beats, an electrical signal is transmitted through the heart muscle in order for it to contract. The transmitter picks up this signal and sends it to the wrist receiver, which displays the data.