Features： 1、With colorful OLED display, rapid oxygen saturation reading. 2、Alarm limit can be set manually, meeting different demands. 3、Automatically power off when no signals after 8sec, convenient to use. 4、Four directions display by manually changed, you can adjust according to your need. 5、Accurately monitoring even in low perfusions 0.4%; Audible, visual alarm and low voltage indicator are available. Specification： Item Type: Fingertip Pulse Oximeter Material: ABS Blood Oxygen Saturation (SPO2) Measurement Range: 35% -99% Resolution: ± 1% Measurement Accuracy: 90% -99%: 1% ≤70% undefined Alarm default value: <85% Pulse Rate (PR) Measurement Range: 30bpm-240bpm Resolution: + 1bpm Alarm Default:> 110bpm Upper Limit Setting Range: 100-250bpm, Lower Limit Setting Range: 15-95bpm Pulse Rate (PR) Alarm Limit Setting: Stand-Alone: ± 5 Blood Oxygen Saturation (SpO2) Alarm Limit Setting: Stand-Alone ± 1 Battery: 2 x AAA Battery (Not Included) Instructions: 1. Install the battery. 2. Fully insert your finger into the rubber channel, and then release the clamp to start the test. 3. Don't shake your hand when measuring, otherwise the measured value will be unstable. Package List： 1 x Fingertip Pulse Oximeter