Introducing Oura Ring 4: the latest evolution of the revolutionary smart ring. Oura Ring 4 brings you closer to what matters most — your health. The updated all-titanium design is powered by Smart Sensing, a new sensing platform that doesn’t just measure your biometrics, it adapts to you, providing insights into over 30 biometrics including sleep, readiness, activity, heart health, stress, and women’s health. Oura Ring 4 quietly and comfortably monitors your health and with up to 8 days of battery life — you can forget it’s even on. Sleeker, smarter and more accurate than ever, Oura Ring 4 is made for you. Oura Ring 4 is FSA/HSA Eligible — we can accept FSA or HSA funds for the following: Oura Ring 4, additional chargers, and shipping. IMPORTANT: Size yourself with the Oura Ring 4 Sizing Kit before you buy — Oura Ring 4 is not US standard sizing, and finding the right size will result in the best experience possible. With an Oura Ring 4 sizing kit purchase, a $10 credit will automatically be applied to your Oura Ring 4 at checkout.