Support 6 display modes (include big font mode). Lightweight and Easy-To-Use. Color OLED simultaneously displays for testing value and plethysmogram. Adjust the parameters in friendly menu. Manually adjust the direction of interface. Low battery voltage indicator. Visual alarm function. Automatically switch off while no signal. Standard two AAA 1.5V alkaline batteries support more than 30 hours continuous work. Advanced DSP algorithm inside decreases the influence of motion artifact and improves accuracy of low perfusion. Anti-Movement, more stable.