Features 1、Multiple Functions: The smart ring has multiple functions, which can monitor your heart rate, temperature and blood oxygen at any time, so that you can observe your health at any time. 2、Lightweight Design: The ultra light body of the smart ring has no sense of wearing. The wearing experience is so light that you may forget its existence. 3、Detect Sleep Quality: This smart ring can detect your sleep time and sleep state during your sleep to tell you how your sleep quality is. 4、Sports Ring: Smart health ring can also be a sports ring, because it can record your steps in a day, providing you great using experience. 5、Smart Ring Material: The smart ring is made of aluminum alloy and ceramic, which is sturdy, beautiful and elegant. 6、Ideal Gift: This smat ring is a meaningful gift. It is suitable for any scene or holiday, such as birthday, anniversary, Thanksgiving, Christmas, Hanukkah or Valentine's Day. Item Type: Smart Ring Material: Aluminum Alloy, Ceramic, Electronic Components Battery Type: Lithium Battery (Shipped With Built In Battery) Battery Quantity: 18mAh Duration: 3-5 Days Charging Time: 45 Minutes Protection Grade: IPX8 Suitable size: Ring Number: 17, Finger Circumference: 52.12mm, International Code/US Code: 5.5/6/6.5, Inner Diameter: 17MM Ring Number: 18, Finger Circumference: 55.26mm, International Code/US Code: 7/7.5, Inner Diameter: 18MM Ring Number: 19, Finger Circumference: 58.4mm, International Code/US Code: 8/8.5, Inner Diameter: 19MM Ring Number: 20, Finger Circumference: 61.54mm, International Code/US Code: 9/9.5/10, Inner Diameter: 20MM Ring Number: 21, Finger Circumference: 64.68mm, International Code/US Code: 11/11.5, Inner Diameter: 21MM Ring Number: 22, Finger Circumference: 67.82mm, International Code/US Code: 12/12.5, Inner Diameter: 22MM Package List 1 x Ring 1 x Charging Cable 1 x Manual