Large AMOLED Display1.72-inch AMOLED screen with 212x520 resolution and full-touch support, featuring a 1500nits brightness for clear visibility even in bright sunlight. Premium DesignElegant symmetrical aesthetics with a 2.0mm ultra-narrow bezel, 2.5D reinforced glass, and aluminum alloy middle frame combined with high-strength polymer fiber. Advanced Health Monitoring24/7 health tracking including blood oxygen, heart rate, and sleep monitoring, powered by a self-developed adaptive physiological perception algorithm for more accurate sleep detection. Comprehensive Fitness TrackingOver 150 sport modes with advanced metrics like VO2 max, recovery time, training effect, and training load. Features AI swim stroke recognition and 9-axis posture detection for 95% accuracy in swim lap counting. Bluetooth-compatible Heart Rate BroadcastingReal-time heart rate data can be sent to cycling computers, allowing users to monitor their heart rate without raising their wrist, enhancing convenience and safety. Water Resistance5ATM water resistance rating, suitable for swimming and other water activities. Specifications: Model: M2457B1 Display: 1.72-inch AMOLED, 212x520 resolution Screen Brightness: 1500nits with auto-adjustment Materials: 2.5D reinforced glass, aluminum alloy frame, high-strength polymer fiber Sensors: Accelerometer, gyroscope, geomagnetic, optical heart rate, blood oxygen, ambient light Water Resistance: 5ATM Wireless Connectivity: Bluetooth-compatible 5.4 Vibration Motor: Linear motor Battery: 233mAh lithium-ion polymer Charging Time: Approx. 60 minutes Adjustable Wristband Length: 135-210mm Wristband Material: TPU Supported Languages: Simplified Chinese, Traditional Chinese, English Compatible Systems: Android 8.0 and iOS 14 or above Supported App: Mi Fitness Dimensions: 46.57 x 22.54 x 10.95mm Weight: 15.95g (without strap) Package included: 1 x Smart Bracelet 1 x Charging Cable 1 x Chinese Instruction Manual