DISPLAY Type Retina LTPO OLED, 2000 nits (peak) Size 1.9 inches Resolution 484 x 396 pixels (~326 ppi density) Build Glass front, ceramic/sapphire crystal back, stainless steel frame IP6X certified 50m water resistant ECG certified, HW certified Protection Sapphire crystal glass Always-on display PLATFORM OS watchOS 10, upgradable to watchOS 10.2 Chipset Apple S9 CPU Dual-core GPU PowerVR Internal 64GB SOUND Loudspeaker Yes COMMS WLAN Wi-Fi 802.11 b/g/n, dual-band Bluetooth 5.3, A2DP, LE Positioning GPS, GLONASS, GALILEO, QZSS, BDS NFC Yes FEATURES Sensors Accelerometer, gyro, heart rate, barometer, always-on altimeter, compass, SpO2, VO2max, temperature (body) Temperature sensing (0.01˚ accuracy) Ultra Wideband 2 (UWB) support BATTERY Type Li-Ion 308 mAh, non-removable Charging Wireless, 0-80% in 45 min (advertised)