Product Features: 1. Display Format & Range: LCD SPO2:50-99% in two-digit 7-segment digital display. Pulse Ratio:30-240 BPM in 3digit 7 segment digtal. Pulse Wave: 6-segment bar graph. Battery Voltage Low Indication: Segment LCD Signals. 2. Power Requirement: Two AAA Size 1.5V Alkali Battery. 3. Power Consumption: Less than 40mA, Voltage:2.6V~3.3V 4. Resolution: 1% for SPO2 and IBPM for Pulse Ratio. 5. Measurements Accuracy: 2% in stage of 70%. 2 BMP for Pulse Ratio. 9. Dimension: 66(L) X 36(W) X33(H) mm. 10. Gross Weight: 50 grms.