Renpho - Smart Ring Health Tracker, Sleep Activity Monitor Long Battery No Subscription Titanium - Black - (2025)

Since the size of a Lynx smart ring differs from standard jewelry ring sizes, please purchase a sizing kit to find your perfect size and then purchase the Lynx health smart ring. The sizing kit includes 8 ring sizers (sizes 6-13) and a quick-start guide for this measuing tool to help measure your ring size more accurately.

Track your sleep, activity, and heart rate without any monthly fees. This smart ring measures your heart rate automatically every 30 minutes and provides real‑time sleep cycle analysis, step count, calories burned, and exercise performance. The built‑in battery lasts 2‑3 days, and the included charging case extends total use to over 10 days. It’s waterproof up to 80 meters – wear it while swimming, sweating, or washing hands. No app subscription needed – full features are free forever. Works with iOS and Android. Before ordering, please measure your finger circumference using the size chart to ensure a perfect fit. A great choice for anyone who wants continuous health tracking without a bulky watch.

Track your sleep, activity, and heart rate without any monthly fees. This smart ring measures your heart rate automatically every 30 minutes and provides real‑time sleep cycle analysis, step count, calories burned, and exercise performance. The built‑in battery lasts 2‑3 days, and the included charging case extends total use to over 10 days. It’s waterproof up to 80 meters – wear it while swimming, sweating, or washing hands. No app subscription needed – full features are free forever. Works with iOS and Android. Before ordering, please measure your finger circumference using the size chart to ensure a perfect fit. A great choice for anyone who wants continuous health tracking without a bulky watch.