The Oura Ring 4 Silver in size 10 is a pre-owned smart ring designed for fitness enthusiasts, specifically for running and jogging. Made of titanium, this ring includes infrared sensors and is equipped with multi-sport features. It is lightweight at 0.400 lbs and has dimensions of 4.4 x 4.5 x 1.2 inches. The ring is designed to track your fitness activity in English language, providing a unique and stylish way to monitor your workouts.