OLED two-color display with brightness adjustable, SpO2 / PR and perfusion index value display, 70~99% measuring range, ±1% blood oxygen saturation, 30BPM~240BPM pulse rate measuring, ±1BPM or ±1% of the measured value accuracy, 10ºC~40ºC storage temperature, 15%~80% working and 10%~80% storage ambient humidity, 70kPa~106kPa atmosphere pressure, when np finger is inserted, it will automatically shut down after 8 seconds, six display modes, USB port, one-button operation, audible pulse sound and waveform graphical display, low battery alarm, suitable for use in family / hospital and physical care in sport, 2AAA DC 3V AAA x 2 built-in battery.