parameter: Blood oxygen measurement range: 35%-100% Pulse rate measurement accuracy: plus/minus 2% Blood oxygen saturation measurement accuracy: plus/minus 2% (75-100%) Blood perfusion index measurement accuracy: plus/minus 0.1% Size: W:74mm*D:29mm*H:145mm Power: 3*AAA batteries (not included in our package) About it: 1: The second-generation LFC PLUS light-frequency digital conversion technology is adopted, which greatly improves the measurement accuracy in the case of exercise and weak perfusion (low blood flow at the measurement point, common in the elderly); 2: Rich detection functions: SpO2, PR, PI; 3: Alarm function: the upper and lower limits of the alarm are adjustable, as long as you press and hold the switch button for 3 seconds and release it, you will enter the setting interface; 4: The machine supports continuous detection, can store 384 hours of monitoring data, and has the function of trend graph playback;