Features: Health rings: Caring for yourself from the smallest details, the intelligent health rings records every heartbeat, delivering care and concern for your health at every moment. Blood oxygen detection: The portable blood oxygen detection rings easily monitors your blood oxygen saturation, you can ensufe you respiratory health and live. Temperature detection:Real-time monitoring of temperature changes, intelligent warning of abnormal fever, protect your health, keep you comfortable and at ease in any environment. Sleep recommendations: Detect health data around the clock and uploading it to the app in realtime to give accurate health advice. Heart rate detection: 24hrs/7-day heart rate monitoring, capturing every heartbeat, allow you to know your heart rate changes and guard your heart health. Motion monitoring: indoor running, outdoor running, treadmillfitness walking... Lightweight and thin: craft from quality materials, feel virtually no weight on your finger yet monitors your vital health around the clock, ensuring you are always at your best. Specifications: Material: stainless steel Color: white, black(optional) US Size: 8, 9, 10, 11, 12, 13(optional) Size 8 Inner Diameter: about 18.1mm/0.71" Size 9 Inner Diameter: about 18.9mm/0.74" Size 10 Inner Diameter: about 19.8mm/0.78" Size 11 Inner Diameter: about 20.6mm/0.81" Size 12 Inner Diameter: about 21.4mm/0.84" Size 13 Inner Diameter: about 22.2mm/0.87" Package Includes: 1pc SQ666 Finger Rings(only 1pc) note: Please allow 1-2cm errors due to manual measurement. Please allow for slight color differences due to different display resolution.