A full charge can be used for 3-5 days for a typical scenario, so the smart watch has long standby and is power-saving. Not only does this smart watch monitor your heart rate changes 24 hours, but it also measures blood pressure, which helps you understand long-term changes in your health problems. It is made of high-quality plastic and metal material, which is lightweight and portable. The diameter of the watch dial is 42.5mm and the thickness is 9.5mm. It is suitable for daily wear, running, sports, outdoor, travel and so on. Item Name: Smart Watch Material: Plastic, Metal Model: D18S Display Type: Color LCD With Removable: Yes Screen Size: 1.44 Inch Resolution: 240 x 240 Pixels Battery Power: 150mAh (Included) Standby Time: About 3-5 Days Charging Time: 1-2 Hours Compatible System: for iOS and for Android Waterproof Grade: Life Waterproof Grade IP67, Does Not Support Swimming and Bathing Functions: Pedometer, Social Entertainment, Smart Reminder, Remote Control Selfie, Health Monitoring, Information Push, Fitness Tracking, Sleep Analysis Features: Heart Rate Monitoring, Touch Control, Long Standby Size Details: Watch Dial Diameter: 4.25cm/1.67" (Approx.) Watch Dial Thickness: 0.95cm/0.37" (Approx.) Notes: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Package Includes: 1 x Smart Watch 1 x User Manual