A fingertip pulse oximeter is a device that measures the oxygen saturation of a person's blood (SpO2) and their pulse rate. It is a small, portable device that is placed on a person's fingertip to obtain the reading. The device uses two light-emitting diodes (LEDs) and a photodetector to measure the amount of oxygen in the blood.

To use a fingertip pulse oximeter, follow these steps:

Turn on the device and insert your finger into the designated opening.
Make sure your finger is positioned correctly in the device, with the LED lights in contact with the skin.
Wait a few seconds for the reading to be displayed on the screen.
It is important to note that pulse oximeter readings may be affected by factors such as poor circulation, low blood pressure, or nail polish, so it may be necessary to take multiple readings or use a different finger. Also, it is important to note that it should not be used as a substitute for professional medical advice.

It is a non-invasive way of measuring the oxygen saturation in a person's blood, which can be useful in a variety of settings, including hospitals, clinics, and at home. It can also help monitor the effectiveness of treatment for conditions such as asthma, COPD and other respiratory conditions.