The smart ring is made for active people. Always check your health status using the ring provided by us. Attention! For the safety of a suitable ring size and to avoid a possible return, please strictly follow the steps below. How do you find out your ring size? Cut a thin strip of paper or use a non-slip ribbon. Wrap the strip/ribbon around the finger you want to use the ring on, making sure it is perfectly tight. The ideal size for a ring is when it can be rotated without falling off the finger. Make a mark where the wrapped paper or ribbon touches the free end. Using a ruler, measure the length of the paper, from the free end to the mark you made. This size represents your size. Attention! When measuring the circumference of the finger, errors can occur that affect the accuracy of the result. Too loose a grip on the band significantly alters the real value. Specifications: Material: stainless steel; Application: QRing; Ring size: 11; Finger circumference: 64.7mm; Ring diameter: 20.6mm; Usage time: 6 days; Application: QRing; Compatibility: Android, iOS; Functions: exercise monitoring, pulse monitoring, oxygen saturation monitoring, stress test, calorie monitoring, pedometer and sleep monitoring, menstrual cycle calendar. The package includes: smart ring, power cable.