The device is an electrocardiograph which can collect 12-lead ECG signal simultaneously and print ECG waveform with thermal printing system. It features in, recording and displaying ECG waveform in auto / manual mode; measuring, analyzing and diagnosing ECG waveform parameters automatically; prompting for “Lead off” and “Lack of paper”; optional interface language (Chinese / English, etc.); built-in lithium battery, AC / DC; selecting rhythm lead freely to observe abnormal heart rhythm; case database management.