Sinceda Unisex Children Multi Function Luminous Analog Digital Electronic LCD Watch Waterproof Japanese Original Automatic Movement & 3volt CR2025 battery (for about 3 years) Water Resistancy: Up to 30 Meters, 1/100 second Stopwatch Movement: Double Formats 12/24 Hour show; Hour, Minute,Second, Day, Week, Month Dial: Length: 3.8 Width: 3.8 Thickness: 1.5 (CM) Strap: Silica Gel