The device can be used to painlessly measure the oxygen saturation of the blood dye (hemoglobin) that carries oxygen in the blood vessels. No blood sampling is required for the measurement, the subject does not need to be punctured. Easy to use and convenient. Due to its low weight, it provides continuous monitoring almost unnoticed. The device continuously displays the measured value by pinching it with your finger. Can be used in both adults and children. It is also suitable for home use and use in healthcare facilities.