Apple Watch Series 4 GPS, 44mm Space Gray Aluminum Case, Black Sport Band: S4 with 64-bit dual-core processor (Up to 2x faster than S3 processor) Electrical heart sensor (ECG app) Water resistant to 50 meters LTPO OLED Retina display with Force Touch (1000 nits brightness) Wi-Fi (802.11b/g/n 2.4GHz) Bluetooth 5.0 Optical heart sensor Ambient light sensor Capacity: 16GB2 GPS Over 30% larger display Electrical and optical heart sensors Digital Crown with haptic feedback 50% louder speaker S4 SiP with faster 64-bit dual-core processor Improved accelerometer and gyroscope for fall detection Swim proof WatchOS 5 Aluminum case Selection may vary; see a sales associate for available models.   Apple Watch Series 4 (GPS) requires an iPhone 5s or later with iOS 12 or later. (1) Apple Music requires a subscription (2) Compared with the previous generation (3) ISO standard 22810:2010. Appropriate for shallow-water activities like swimming. Submersion below shallow depth and high-velocity water activities not recommended. What's Included: Refurbished Apple Watch Series 4 Magnetic Charging Cable USB Power Adapter