• Keep balance during the test, don't shake up and down, don't exercise vigorously, and keep calm1. Color: Black / Blue2. Material: ABS3. Size: About 6x3.5x3.5cm.4. It can monitor blood oxygen saturation and pulse parameters. And there is a pulse pulse diagram display.5. Automatic shutdown function in about 8 seconds when there is no signal.6. Use two AAA batteries, low power consumption.7. The product is light, small in size and easy to carry.8. Easy to use, one-key operation.