Features: Multi-function: Digital pulse oximeter can be used to measure pulse rate, blood oxygen saturation levels accurately. Easy to Read: Support SpO2, pulse, and bar chart, you can view your result very clear with LED display. Easy to Use: Accurate and reliable, one button operation, just clip it on to your finger and turn it on at the press of a button. Automatic power off after 5s when not in use. Widely Applicable: Suitable for everyday use. Widely used in family, physical care in sports, etc. Compact Size: The oximeter is lightweight and portable. Specifications: Model: SO811C Color: black Material: Plastic Display Mode: LED display Blood Oxygen Measurement Range: 0% ~ 99% (resolution is 1%) Blood Oxygen Measurement Accuracy: 70 ~ 99%, ± 2%, less than 70% undefined Pulse Rate Measurement Range: 30BPM ~ 250BPM (resolution is 1BPM) Pulse Rate Accuracy: ±2bpm or ±2% to the maximium Battery: 2 * AAA Batteries (Not included) Working Voltage: DC 3.0V Package Size: 80 * 60 * 38mm