The Oura Ring 4 Smart Ring Activity Tracker in Size 14 in Stealth is a high-tech fitness device designed for both indoor and outdoor activities. With a sleek black design and a durable titanium construction, this activity tracker is equipped with advanced sensors such as SpO2, accelerometer, and GPS. It provides detailed measurements for heart rate, time, calories, and distance, with a battery life of up to 7 days. Compatible with both iOS and Android operating systems, this activity tracker offers features such as Bluetooth connectivity, temperature monitoring, and a variety of tools for tracking your workouts and monitoring your sleep patterns. Perfect for unisex adults looking to enhance their fitness and wellness.