This oximeter is designed for sports and aviation use, and is not a medical device. Features 1)Display of SpO2 value. 2)Display of pulse rate value. 3)Display of heart rate value 4)Display of step number and calorie. 5)Low-battery indication. 6)Data storage function. 7)The data stored can be wireless uploaded to mobile terminal. 8)Clock function. 9)Charging function. 3.Performance 1)Measurement range of SpO2: 0%~100%, error: 70%~100%: ±2%; 0%~69%: unspecified; 2)Measurement range of pulse rate: 30bpm~250bpm, error: ±2bpm or ±2%(select the larger); 3)Measurement range of heart rate: 30bpm~300bpm, display error is ±1bpm or 1%(select the larger); 4)Resolution：SpO2 : 1%, Pulse rate: 1bpm; 5)Measurement Performance in Weak Filling Condition:SpO2 and pulse rate can be shown correctly when pulse-filling ratio is 0.4%. SpO2 error is ±4%, pulse rate error is ±2 bpm or ±2% (select larger); 6)Resistance to surrounding light: The deviation between the value measured in the condition of man-made light or indoor natural light and that of darkroom is less than ±1%; 7)Pedometer range: 0~65535steps (resolution: one step); 8)Operating Current: ≤100mA; 9)Power supply: built-in rechargeable lithium batteries, voltage is 3.7V; 10)The degree of protection against electroshock: type BF applied part; 11)The grade of protection against ingress of liquid: IP54.