Product model: F57L Screen size: 1.91 inches, 280 x 320 pixels Battery capacity: 260mAh App operating system: iOS 9.0 or above, Android 4.4 or above Charging method: Magnetic suction charging cable Band color: Metal black, champagne gold Specifications: 1. 1.91-inch high-definition large screen with high color gamut, ultra-narrow bezel, and vibrant display. Rich colors and realistic visuals. 2. Supports over 50 sports modes with precise real-time heart rate monitoring and intelligent algorithm. Tracks movement data in real time for efficient and safe workouts. 3. Built-in optical heart rate sensor enables 24-hour heart rate monitoring. LED light on the back detects blood flow changes for accurate readings. 4. Equipped with advanced PPG bio-tracking optical sensor for blood oxygen monitoring. Helps assess body condition after exercise or when feeling fatigued. 5. Wrist temperature monitoring with 24-hour temperature measurement. For accurate results, ensure the sensor is in full contact with the skin after wearing for 10 minutes. Note: Readings may be affected by ambient temperature and are intended for reference only. Package Included: 1 x Bracelet 1 x Charging cable 1 x User manual