Glunovo i3 CGM readings are taken from interstitial fluid, and not from blood, like fingersticks. Interstitial fluid is the fluid that surrounds the cells of the tissue below the skin, and usually, glucose moves from blood vessels and capillaries first and then into the interstitial fluid. It’s helpful to think about it like a rollercoaster where the front car is the blood glucose (BG) and the car in the back is the Glunovo i3 CGM reading: When on the rise, the BG value is greater than the Glunovo i3 CGM reading that follows behind it. But when moving down the tracks, the BG in front is now less than the Glunovo i3 CGM reading.