Overall these images of the as-yet-unannoucned Oura Ring 3 are fairly similar to the Ring 2. The biggest difference appears to be more LEDs on the inside of the band. This may indicate that the new Oura Ring 3 could track heart rate during a workout or track blood oxygen levels. The Oura Ring 2 only includes 3 sensors: Infrared photoplethysmography sensors (PPG) for heart rate and respiration, Negative temperature coefficient (NTC) sensor for body temperature, and 3D accelerometer for movement.