Oura Ring 4 sizes are slightly different from standard ring sizes, so it is important to size yourself using our tools and to follow our sizing instructions. The Oura Ring 4 Sizing Kit allows for you, and those around you, to find the ideal fit before purchasing. You can also size yourself in stores where there is an Oura Ring 4 display. A properly fitting Oura Ring will result in the highest possible data accuracy, comfort, and overall experience. | Oura | | Ring 4 Sizing Kit | Size Before You Buy the OR4 | Unique Sizing | | 2024) | White | Best Buy