Feature: 1. Large Button: Calculator is made of bamboo wood in plain style. The numbers are engraved on the bamboo block and will not disappear. Scientific large button design, in line with human habits. 2. Large Screen: Functional desktop calculator is a 12 digit LCD screen with clear display of large numbers, easy to read from a distance, easy to use. 3. Dual Power Supply: Calculator is dual powered by solar and battery with button batteries that do not need to be replaced for at least two years. It will automatically turn off the power if it is not operated for 5 minutes. 4. Durable: Functional desktop calculator is made of new durable material, bamboo wood carefully carved, small and beautiful, easy to carry, 18 buttons, very practical. 5. Widely Use: Solar Calculator is a paperless calculator, perfect for office, business, student, store, mall daily and home use. Specification: Item Type: Solar Calculator Material: Bamboo Number Of Keys: 18 Keys Production Process: Engraving Battery Type: CR2032 Button Cell (Built In) Battery Capacity: 240mAh Size: Approx. 170x82x19mm / 6.7x3.2x0.7in. Package List: 1 x Calculator1 x Instruction Manual Note: Manual measurement, please allow slight error.