41mm (1.69") 430x352pixels, 904sq mm display area, Always-On Retina LTPO OLED display, Up to 1000 nits brightness 32GB 1GB RAM, Apple S8 SiP with 64-bit dual-core processor, W3 Apple wireless chip, U1 chip (Ultra Wideband), PowerVR GPU watchOS 9.0, upgradable to 9.3, 282mAh Battery, Wi-Fi 802.11b/g/n 2.4GHz and 5GHz, Bluetooth 5.3, 50m Water-resistant Temperature sensing, Blood Oxygen and ECG app, Fall Detection, Emergency Calling, Cycle Tracking, Irregular rhytModazone and Cardio fitness notification 2G: 850/900/1800/1900, 3G: 850/1700(AWS)/1900/2100, 4G LTE: 1/2/3/4/5/6/7/8/18/19/20/25/26/28/39/40/41/66 - eSIM. Cellular LTE model Compatible with GSM and CDMA Carriers like T-Mobile, AT&T, Verizon, etc. Contact Carrier to Register. Wireless comm standard: 2.4 ghz radio frequency Water resistance level: water resistant Water resistance depth: 50.0 meters