COLMI R02 Smart Ring, size 8, 18.1 mm (black) + charging case

COLMI R02 Smart Ring, Size 8

The black COLMI R02 Smart Ring in size 8 (18.1 mm inner diameter) combines health monitoring with sports and activity tracking. It measures heart rate and blood oxygen saturation (SpO2), monitors sleep and tracks daily activity and workouts across 21 sports modes. Bluetooth 5.0 connects the ring to the QRing app, while onboard memory stores data for later synchronisation. IP68 water resistance and the included charging case support convenient everyday use, with a battery life of 6–7 days per charge.

Compact design and comfort

Designed for comfortable everyday wear, the ring weighs approximately 4.7 g and is 2.7 mm thick. Its lightweight, discreet design allows natural hand movement and is suitable for writing, physical work and exercise. It can be worn day and night to collect activity and sleep data continuously.

Health and vital-sign monitoring

The COLMI R02 automatically monitors heart rate and blood oxygen saturation (SpO2) in the background. Data is stored in the ring, so measurements can be synchronised with the app later, even when your phone is not with you. The app lets you review results in context and follow changes over time.

Sleep and recovery analysis

Automatic sleep tracking records total rest time and identifies sleep stages, including light and deep sleep. Data is stored locally and can be synchronised with the app in the morning, so sleep tracking does not require a constant phone connection.

Sports modes and activity tracking

The ring offers 21 sports modes for activities such as walking, running and general training. It tracks steps, distance, calories burned, workout duration and heart rate, helping you review activity and follow progress over time.

Connectivity and compatibility

Bluetooth 5.0 provides wireless communication with the QRing app, where synchronised data is presented for review. The ring is compatible with Android 4.4 and later, iOS 8.0 and later, and HarmonyOS.

Charging case and battery life

The included case provides storage and charging. Place the ring in its designated position to charge it through magnetic contacts. Battery life is approximately 6–7 days, and a full charge takes about one hour. A magnetic cable is included.

Materials and water resistance

The outer casing is made from titanium alloy for resistance to scratches and everyday wear. The inner lining is hypoallergenic resin, designed to support comfortable wear and reduce the risk of irritation. IP68 water resistance allows the ring to be worn while washing your hands, exercising or coming into contact with water.

Choosing the right size

For a comfortable fit and reliable measurements, choose the correct ring size. Measure around your finger with a thin string or thread, mark where the ends meet, and compare the length with the size chart. Available sizes are 8 (18.1 mm inner diameter), 9 (18.9 mm), 10 (19.8 mm) and 11 (20.6 mm). Measuring in the evening may help account for natural changes in finger size during the day.

Specifications

• Manufacturer: COLMI
• Model: R02
• Size: 8
• Inner diameter: 18.1 mm
• Circumference: 56.9 mm
• Colour: Black
• Outer material: Titanium alloy
• Inner material: Hypoallergenic resin
• Thickness: 2.7 mm
• Weight: Approximately 4.7 g
• Health and monitoring features: Heart rate measurement, blood oxygen saturation (SpO2) measurement, sleep monitoring, activity monitoring and activity-level monitoring
• Sports modes: 21
• Recorded data: Activity time, distance, calories and heart rate
• Connectivity: Bluetooth 5.0
• App: QRing
• System compatibility: Android 4.4 and later, iOS 8.0 and later, HarmonyOS
• Charging case: Yes; charging and storage
• Water resistance: IP68

Included

• COLMI R02 ring
• Charging case
• Magnetic cable
• User manual