... use with one-key operation * Accurately measure SpO2 value and Pulse Rate value;* Large True color OLED display of SpO2, ... PR, Pulse Bar,PI & Plethysmogram;* Multi-direction display, various display modes ( ... ;* Audible & visible alarm function, high & low alarm limits adjustable;* Pulse beep function;* Low battery voltage indication. Fingertip Oximeter