DATA SPESIFICATION : Spo2 - Range : 50%-100% - Accuracy : ? ±2%(90%-99%), ? ±4%(70%-89%), ? ±6%(50%-69%) - Method : Dual wavelength LED Pulse Rate - Range : 30-250bpm - Accuracy : ±1bpm Battery Type : 1.2VX5pcs rechargeable NiMH batteries 2000-2300mAh Life : Approximately 20 hours for normal Measurement status Alarm : Low power light alarm