Digital oximetryis an inexpensive and accurate way to measure pulse rate and degree of saturation. lt also shows the volume waveformThe map guarantees accuracy. Small size, easy to carry. Sp02 PR Features Packaging & Delivery Measurement range:70--99% Resolution:1% Accuracy:2%(70%-99%)unspecified (<70%) Measurement range: 30-240 bpm Resolution:1% Accuracy: 2bpm or 2% (select larger) Low Perfusion <0.4%Power. 1.5V (AAA size) alkaline battery x 3 (Not included)Supply voltage:4.5-5V 1. 24 inch high-resolution LCD screen with 9 adjustable brightness displayeffect is clearer in different environment2 Intelligent parameter monitoring interface.Real-time display values and waveforms. 3.Low perfusion <0.4%. Anti-interference. Detection is simpler and moreaccurate. 4.Probe optional, applicable to Adult Child and Neonatal patients Shows Sp02and PR 820mini outer box: