We aim to show you accurate product information. Manufacturers, suppliers and others provide what you see here, and we have not verified it. See our disclaimerTHIS ITEM IS REFURBISHED. Measure your workouts, from running and cycling to high-intensity interval training. Track and share your daily activity, and get the motivation you need to hit your goals. Better manage everyday stress and monitor your heart rate more effectively. Automatically sync your favorite playlists. And stay connected to the people and info you care about most. GPS and a barometric altimeter track how far and high you go. Dual-core processor for faster app performance. Ultimate sports watch and intelligent activity tracker. Swimproof so you’re always ready for the pool or ocean. Aluminum case watchOS 4 is even more intuitive and intelligent. Apple Music requires a subscription. Compared with the previous generation. Appropriate for shallow-water activities like swimming. Submersion below shallow depth and high-velocity water activities not recommended. Key Features:  Aluminum Chassis with Ion-X Glass 1.5″ 340 x 272 1000-Nit Display Activity and Heart Rate Monitoring Changeable Faces with Widgets Siri Integration Displays Notifications and Runs Apps Water Resistant to 164′ Integrated GPS Bluetooth 4.2, 802.11b/g/n Wi-Fi Apple watchOS 4.0 Specifications: Watch Operating System: watchOS 4.0 Compatible Operating System: iOS 11 and later CPU: Apple S3 Dual-Core GPU: PowerVR RAM: 768 MB Storage: Capacity 8 GB Sensors: Accelerometer, Altimeter, Barometer, Compass, Gyroscope, Heart Rate and Light Sensor Connectivity: Bluetooth, Wi-Fi, NFC Dial Shape: Rectangle Display Technology: OLED Display Resolution: 272 x 340 Pixel Density: 326 PPI