Oura - Ring 4 Ceramic - Smart Ring - Size Before You Buy with OR4 Sizing Kit - Size 8 - Midnight - (2025)

Specifications

• Operating System Compatibility

  Apple iOS, Android
  Built-in Storage

  0 gigabytes
  Metrics Measured

  Activity vs. inactivity, Blood oxygen, Hours slept, Calories burned, Resting heart rate
  Protective Qualities

  Dust resistant, Water resistant
  Maximum Depth of Water Resistance

  328 feet
  Band Material

  Ceramic