APPLE WATCH SERIES 6 GPS,44MM ALUMINUM CASE,WHITE SPORT BAND,WATCH OS,SILVER,USED

The future of health is on your wristMeasure your blood oxygen level with a revolutionary new sensor and app. Take an ECG anytime, anywhere. See your fitness metrics at a glance with the enhanced Always-On Retina display. With Apple Watch Series 6 on your wrist, a healthier, more active, more connected life is within reach.Blood Oxygen A breath of fresh innovationYour blood oxygen level is a key indicator of your overall wellness. It can help you understand how well your body is absorbing oxygen, and the amount of oxygen delivered to your body. The remarkable new sensor and app in Apple Watch Series 6 allow you to take on-demand readings of your blood oxygen as well as background readings, day and night.New sensor. New insights. The new blood oxygen sensor is made up of four LED clusters and four photodiodes. Incorporated into the completely redesigned back crystal, this new sensor works in concert with the Blood Oxygen app to determine your blood oxygen level.Deeply illuminating. Green, red, and infrared LEDs shine light onto the blood vessels in your wrist, and photodiodes measure the amount of light reflected back.