Oura Ring 4 Black

Sensors

- Red and infrared LEDs measure blood oxygen levels

- Green and infrared LEDs alternate to measure heart rate, heart rate variability (HRV), and respiration rate 24/7

- Digital sensor measures temperature trends

- Accelerometer tracks movement and activity 24/7

Compatibility

- Oura App available in English, Finnish, Japanese, German, French, Spanish, Italian, Norwegian, Swedish, Czech, Dutch, and Danish

- Supports metric and imperial units of measurement

- Integrates with 40+ apps

- Compatible with iOS and Android

Weight and Dimensions

- Width: 7.90 mm

- Thickness: 2.88 mm, similar to a wedding band

- Weight: 3.3–5.2 g, depending on ring size

Battery Life

- 5–8 days of battery life*

- Typically charges in 20–80 minutes, depending on battery level

Quality Materials

- Non-allergenic titanium on inner and outer surfaces

- Seamless titanium interior

- Water resistant up to 100 m (328 ft)

- Minor scratches from regular wear are normal

Connectivity

- Bluetooth Low Energy

- Automatic firmware updates via the Oura App

- EMF-safe

- Supports airplane mode

- FCC-certified