The BERING Slim Solar collection beats to the rhythm of nature! Because its energy source is environmentally friendly and infinitely available: light! Not only sunlight but any kind of light is converted into electrical energy by the solar cell under the face and stored in a rechargeable secondary battery. No battery change is required as in quartz watches. The watch has a power reserve, so that - once fully charged – it runs for 6 to 12 months. Even if it is stored in complete darkness during this time. Scratch resistant sapphire crystal, brushed stainless steel, the finest straps in mesh. Number of Batteries: 1 Features: Crystal Accent, Water Resistant, Quick Ship Jewelry Closure: Buckle Power Source: Battery (included), Ecodrive Watch Movement: Quartz Water Resistance: 50m Band Color: Blue Dial Color: Mother of Pearl Metal Color: Blue Case Thickness: 7mm Case Width: 27mm Band Content: Stainless Steel Case Materials: 100% Stainless Steel Band Width: 15mm Care: Wipe Clean Band Type: Metal Link Country of Origin: Imported Quick Ship items ship directly from the manufacturer within 3 to 5 business days. Photos are enlarged to show detail.