Certified digital fingerprint oximeter with large screen. Measures oxygen levels very easily and quickly and directly measures oxygen saturation in your blood and heart rate. It is suitable for patients with heart problems, pneumonia and people who exercise and can their oxygen level is reduced during exercise. It is easy to use, you put your finger in the socket and you can immediately see the indications. It comes with its box and with a carrying cord. It works with 2 alkaline AAA batteries. (Not included).