The Haylou Solar 5 BT Calling Smart Watch features a 1.58-inch AMOLED display, a dual-core processor, and Bluetooth 5.3 connectivity for making calls. It includes a range of health sensors and supports over 100 sports modes. Display and design Display: 1.58-inch AMOLED with 480 x 480 resolution. Refresh rate: 60Hz for smooth visual performance. Brightness: Up to 1000 nits, ensuring visibility in bright sunlight. Always-On Display (AOD): Supported. Design: 2.5D curved screen with a military-grade alloy middle frame. Weight: Approximately 131g (including the strap). Strap options: Available with a metallic or silicone strap. Water resistance: IP68 rated, providing protection against dust and water splashes.  Performance and battery Processor: Dual-core processor. Bluetooth: Version 5.3. Bluetooth Calling: Allows users to make and receive calls directly from the watch. NFC: Supported for access control systems. Battery capacity: 360mAh. Battery life: Up to 15 days under typical usage and up to 40 days in long battery life mode.  Health and fitness features Sports modes: Over 100 professional sports modes for various activities, including swimming, cycling, and running. Health monitoring: Includes 24/7 heart rate monitoring, blood oxygen saturation (SpO₂) tracking, and stress tracking. Sleep monitoring: Intelligently detects and records sleep duration, depth, and REM cycles. Female health management: Tracks and predicts menstrual cycles. Reminders: Features include sedentary reminders, water-intake reminders, and medication reminders.  Smart and convenience features Storage: Supports storage for up to 50 album photos and local offline music (up to 10 songs). Built-in Recorder: Provides up to 70 minutes of recording time. Other features: Offers customizable watch faces, quick replies to messages, music control, and a voice assistant. Compatibility: Requires Android 9.0 or later or iOS 11.0 or later.