Feature 1.Portable and easy to use. 2.Manually adjust the interface orientation. 3.The LED display shows both the test value and the bar graph. 4.Low battery voltage indication. 5.Automatic standby. 6.This oximeter contains 2 AA batteries (excluding battery) Product specifications Display: OLED display SP02: Measuring range: 70%-99% PR: Measuring range: 25BPM-250BPM Working temperature: 5 ° C -40 ° C Storage temperature: -20 ° C -55 ° C Working humidity: 15%-85% Package includes 1 pulse oximeter 1 x product brochure 1 x product lanyard 1 x box 1 x cloth bag