The Finger Pulse Oximeter C1 is one of the most widely used. This finger heart rate monitor provides real time measurements of oxygen saturation in the blood. The professional oxygen saturation monitor is ideal for anyone who wants to know their oxygen level. With the ability to test pulse oxygen saturation and pulse rate through your finger, the Finger Pulse Oximeter C1 is simple and quick to use. This finger heart rate monitor is recommended by doctors. Two AAA alkaline batteries are included. This lightweight and compact finger heart rate monitor measures 2.2" long x 1.2" wide x 1.1" high. Finger Pulse Oximeter C1: * 2 AAA alkaline batteries (included) * High-quality LED display * Lightweight & compact design * Automatic shut-off after unit is idle for 8 seconds * Low voltage/battery indicator light * SpO2 range: 0-99% * PP range: 30bpm-235bpm * Dimension and weight: 2.2" x 1.2" x 1.1" and 1.7 oz