Oura Ring Gen 4, size 7, rose gold color. Purchased on 2/9/26. It is a sleek, screenless smart ring that tracks over 50 health metrics, including sleep, 24/7 heart rate, stress, blood oxygen, and menstrual cycles. It features a fully titanium build with recessed sensors for a much more comfortable fit than previous models, plus an improved 8-day battery life. Key updates and features of the Oura Ring Gen 4 include: Smart Sensing Technology: The upgraded internal algorithms adapt to your unique finger structure and skin tone, filling in data gaps and increasing overall accuracy. Redesigned Interior: Gone are the raised sensor bumps of the Gen 3. The Gen 4 features a seamless, fully titanium interior with nearly flush sensors (at 0.3mm recessed), which most reviewers find significantly more comfortable. App Overhaul: The companion app App Store / Google Play provides a streamlined home screen that organizes your Readiness, Sleep, and Activity scores, and even includes experimental AI features like "Aura Advisor" for personalized health coaching. Specs: It is water-resistant up to 100 meters.