Asus VivoWatch SP User Manual page 28

On your ASUS VivoWatch SP, your Pulse O2 level reading appears as a
percentage and color on the graph.
Using the ASUS HealthConnect App for Pulse O2 level reading
On the ASUS HealthConnect app, you will have access to additional details
about your Pulse O2 level readings, including trends over multiple days.
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