Berry pulse oximeter is a portable device to measure SpO2 (bloods oxygen saturation levels). With that, it tells the percentage of your blood is carrying oxygen. It is suitable for household and personal use. This means that is can measure the level of oxygen within the blood, specifically in arterial blood without using any invasive means. The measuring operation is easy and quick. Hence, you just need to place your finger inside the photoelectrical sensor. Then, the accurate measurements will be display on the screen. Besides that, it accurately determines your pulse rate and pulse strength and display it conveniently on a large digital LED display. In addition, it is small size, lightweight and convenient to carry around. Lastly, this device is suitable for all ages, choose one to have a good command of the health of your families and yourself. Packing list: 1 x Berry Pulse Oximeter Note: It operates using two (2) AAA alkaline batteries (not included).