"Yangjiabao", that is, "oxygen saturation forceps", refers to an instrument clamped at the end of a finger in the medical field to detect human oxygen saturation. It is generally believed that normal should not be less than 94%. Abnormal results: less than 94%, less than 94% is insufficient oxygen supply. Suffering from the disease of insufficient blood oxygen supply. Lack of oxygen has a great influence on the body. Pulse oximeter provides a noninvasive method for measuring oxygen saturation or arterial hemoglobin saturation. Pulse oximeter can also detect arterial pulsation, so it can also calculate and inform the patient's heart rate. Pulse oximeter is a kind of medical equipment to measure the arterial oxygen content of patients.