Pulse oximetry is a test used to measure the oxygen level(oxygen saturation) of the blood. It is an easy, painless he pulse oximeter observes a rapid measurement of oxygen saturation level in your body without using needles or taking a blood sample. 1. Display mode: 1.1 inch color OLED screen display2. Display resolution: 96*643. Pulse rate measurement range: 30bpm ~ 250bpm (resolution is 1bpm)4. Accuracy: ±2bpm or ±2% for large values5. Error under weak perfusion: When the pulse filling degree is 0.4%, theoximeter can correctly display the blood oxygen saturation and pulse ratevalues, the blood oxygen saturation error is ±4%; the pulse rate error is ±2bpmor ± 2% takes a large value.6. Resistance to ambient light interference: The measured value of blood oxygenin indoor natural light and existing illumination source is less than ±1%compared with the measured value under darkroom conditions.Order from Jumia and will be delivered at your doorstep7. Power consumption: no more than 30 mA8. Working voltage: DC 3.0V9. Battery: 2 pcs AAA battery 1.5V alkaline