Supported ApplicationFitness Tracker, Sleep Monitor, Voice Assistant, Elevation Tracker, Heart Rate MonitorBrandAppleWireless Communication StandardBluetooth, 5 GHz Radio Frequency, 802.11a/b/g/n, 2.4 GHz Radio FrequencyColorAluminum Case with PRODUCT(RED) – Sport BandConnectivity TechnologyBluetooth, Wi-Fi, NFC, GPSOperating SystemWatchOSBand ColorRedHuman Interface InputTouchscreen, DialScreen Size40 MillimetersWater Resistance LevelWater Resistant

• GPS model lets you take calls and reply to texts from your wrist
• Measure your blood oxygen with an all-new sensor and app
• Check your heart rhythm with the ECG app
• The Always-On Retina display is 2.5x brighter outdoors when your wrist is down
• S6 SiP is up to 20% faster than Series 5
• 5GHz Wi-Fi and U1 Ultra Wideband chip
• Track your daily activity on Apple Watch and see your trends in the Fitness app on iPhone