30 workout modes to record your heart rate and burned calories, inclu<br />SpO2 tracking can detect your blood oxygen saturation level, which is vital to health Sleep monitoring that could record REM, all day nap and sleep breathing quality. All day Heart rate monitoring and alerts<br />Ag+ Antibacterial strap The in-box black TPU strap contains Ag+ antibacterial agent to prevent skin from germs<br />Up to 14 days battery life for normal use. Easily charged with magnetic charging pin ">