This Casio FX-991ES Plus Scientific Calculator is a reliable tool for your calculations. It is equipped with regular key size, battery/solar power source, and handheld size for convenience. The calculator is perfect for business and office use. With its scientific type and various functions, it can handle complex calculations with ease. The calculator is also durable and made by the reputable brand, Casio. Get your hands on this calculator today and simplify your work!