ECG-03: Digital 12-lead, Single/Three channel, 192x64 dots LCD, waveform display, RS232 interface (software is optional), measure report ECG-03A: Digital 12-lead, Single/Three channel, 320x240 dots large LCD, waveform display, 8 sets data memory, RS232 interface and USB interface (software is optional), measure and analysis report (analysis software is optional), ECG-03B: Digital 12-lead, Single/Three channel, 192x64 dots LCD, waveform display, RS232 interface (software is optional), measure and analysis report (analysis software is optional)