The Oura Ring Gen 4 in black, size 6, is a new and sealed activity tracker designed for both indoor and outdoor use. Made of titanium and powered by batteries with a battery life of up to 7 days, it provides measurements for heart rate, calories, and distance. It features Bluetooth connectivity, temperature sensor, altimeter, pedometer, data review, heart rate monitor, and sleep tracker, making it ideal for tracking various fitness activities such as running and jogging. With a 2.4X external display and support for iOS and Android operating systems, this unisex activity tracker offers comprehensive fitness tracking capabilities in a sleek and stylish design.