Wellue O2Ring Smart Ring Pulse Oximeter. Overnight Tracking.
Bluetooth Low Energy wearable ring measures oxygen saturation and pulse rate - nordicsemi.com
Wevolver.com - This ring-based smart pulse oximeter provides continuous key health data such as blood oxygen and heart rate updates with great battery life. Nordic's nRF52832 SoC makes it possible. In the
O2Ring™ Smart Pulse Oximeter for Adults - Creatori – Creatorishop.com