"Full Description:\nThe Ultrahuman Sizing Kit comes with 10 high-grade mock rings to help you find the perfect Ring size. It is the only Sizing Kit that comes with true-to-life colors to help you visualize your preferred Ring color.\n\nFeatures:\n\u003cul>\n\u003cli>Take the Two Night Test: Wear the Ultrahuman Sizing Kit ring over two nights or 48 hours to find your fit. This is an important step in understanding your ring size. The perfect ring size ensures that you have the most accurate readings.\u003c/li>\n\u003cli>Build Quality: While our sizing kit is made of high-grade plastic, the Ultrahuman Ring is crafted from space-grade titanium and coated with tungsten Carbide, your Ultrahuman Smart Ring promises superior quality and durability.\u003c/li>\n\u003cli>Fit Check: You will get highest data accuracy and optimal comfort with a properly fitting Ultrahuman Ring. Here are a few simple ways to assess this — If you rotate the ring on your finger, it should not rotate freely.\u003c/li>\n\u003cli>Size First Before You Buy: Ultrahuman Ring sizes differ from standard ring sizes. Purchase a sizing kit first to get the perfect ring AIR size. Ring AIR is available in 10 sizes from 5-14.\u003c/li>\n\u003cli>Trying the Sizing Ring: It is important to first use the sizing kit to determine the Ring AIR size. Wear the ring such that the engraved size number is toward the palm of your hand.\u003c/li>\n\u003cli>Finding the Correct Finger: For optimal comfort and advanced sleep tracking, we recommend you wear the Ultrahuman Ring AIR on your index, middle, or ring finger.\u003c/li>\n\u003cli>Choose Your Ring: After you've precisely determined your size and preferred color using our sizing kit, head over to SCHEELS to order your Ultrahuman Smart Ring.\u003c/li>\n\u003cli>Color Choice: With the true-to-life color swatches, you can visualize and pick the color you like.\u003c/li>\n\u003c/ul>\n\nSpecifications:\n\u003cul>\n\u003cli>Material: The outer shell is made from fighter jet grade Titanium reinforced with Tungsten Carbide Carbon coating, making it resistant to everyday wear and tear. The inners of the ring is coated with medical-grade hypoallergenic epoxy resin, making it comfortable to wear at all times\u003c/li>\n\u003cli>Compatible with iPhones running iOS 15 or later and Android devices running Android 6 or later.\u003c/li>\n\u003cli>Red LEDs (heart rate monitoring and oxygen saturation)\u003c/li>\n\u003cli>Automatic firmware updates via the Ultrahuman App\u003c/li>\n\u003cli>Non-contact medical-grade skin temperature sensor\u003c/li>\n\u003cli>Rechargeable, non-replaceable 24mAh LiPo battery\u003c/li>\n\u003cli>90 mins to fully charge the Ring from 0% to 100%\u003c/li>\n\u003cli>Thickness: 2.45 - 2.8 mm (varies with size)\u003c/li>\n\u003cli>Infrared Photoplethysmography (PPG) sensor\u003c/li>\n\u003cli>Weight: 2.4 - 3.6 g (varies with size)\u003c/li>\n\u003cli>Infrared LEDs (heart rate monitoring)\u003c/li>\n\u003cli>Green LEDs (heart rate monitoring)\u003c/li>\n\u003cli>Last up to 6 days on a full charge\u003c/li>\n\u003cli>Bluetooth Low Energy (BLE5)\u003c/li>\n\u003cli>6-axis motion sensors\u003c/li>\n\u003cli>EMF radiation safe\u003c/li>\n\u003cli>Width: 8.1mm\u003c/li>\n\u003cli>Style: UHRA\u003c/li>\n\u003c/ul>\n"