The Oura Ring Gen 4 in black, size 15!is an activity tracker ideal for both indoor and outdoor use. Made of titanium and featuring advanced sensors such as an accelerometer, this ring provides accurate heart rate monitoring along with other features like temperature tracking, goal setting, and a calorie monitor. With a battery life of up to 7 days and a 2-year manufacturer warranty, this ring is designed for unisex adults who engage in activities like running and jogging. Compatible with various operating systems, the Oura Ring Gen 4 is a sleek and reliable tool for tracking and improving your fitness levels.size 15! Good condition 
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