Two-way Power: Solar (works only when it is bright) and Battery (included,long battery life.). Automatic shut-down, energy saving and environmental protection. Display: Displays up to 12 digits Extra-large LCD display., humanized 45-angle display design, to ensure that the human body does not feel tired during long-term use. Durable Silicone Button: Good sense of touch, ABS plastic material, Light weight. Reasonable configuration and comfortable operation. Great for home and Office: Performs common math as well as various financial functions, perfect for both adults and students. High-Quality After-Sales Service: Each product has undergone rigorous testing, and quality problems are guaranteed for free for 1 year. If you have any questions, please contact us directly.