POWER – 2*AAA battery.POWER VOLTAGE – 2.4~3.3VSTANDBY CURRENT – <40uAWORK CURRENT – <50mAfbvPOWER ON – Press white button one time, 0.5s StartLOW POWER – Auto shutdown at battery voltage <2.3VNO FINGER – Display “NO FINGER” and shutdown after 10s OVERVIEWOxygen Saturation is the percentage of oxyhemoglobin (HbO2) that is combined with oxygen against all combinable hemoglobin(Hb).The Oxygen saturation of arterial blood in a normal human body is 98%.If the measured value of oxygen saturation islower then 94%, an insufficient supply of oxygen is considered. Hours Seconds Hurry Up..Place Order–Contact – 6301196345