About this item ULTRA-SLIM METAL BODY WITH 3D CURVED BEZEL-LESS DESIGN: Zepp E Circle is equipped with pure black 3D curved bezel-less glass and polished stainless-steel back perfectly fused together, making the watch sleek and ultra-slim. With only 9 mm thickness, it's exceptionally comfortable to wear day and night. BLOOD OXYGEN SATURATION MEASUREMENT: SpO2 is an important indicator of health, especially in high-altitude and low-oxygen environments or while performing high-intensity sports. With Zepp E, you can measure your current blood-oxygen saturation instantly from your wrist. SLEEP QUALITY MONITORING: Monitor light sleep, deep sleep, rapid eye movement (REM), and awake time. It also provides you a score on sleep quality and breathing quality. It even monitors your 20-minute nap during the day. 7-DAY BATTERY LIFE: Zepp E endures for up to 7 days in typical usages mode for a single full charge, which free you from the daily recharge. NOTIFICATIONS AND ALARMS: You will also receive notifications when your heart rate exceeds the recommended limit. Zepp E Circle receives notifications for incoming calls, emails, messages and other applications without having the phone; sedentary reminders if you've been sitting too long. Included components: User Manual Connectivity technology: Bluetooth