In examination, time is the most important resource, and therefore your calculator must compute expression quickly. The latest Scientific Calculator from Casio, fx-991EX Classwiz is 4 times faster than previous model fx-991ES Plus and having 4 times better resolution for easier viewing. ClassWiz has intuitive user interface and high-performance functions, so ideal for education. It is most recommended by teachers across the world for students community from school to college and university level.The key notation, like the display format, uses signs and symbols like those found in mathematics textbooks. This natural interface makes input fast and easy.Unique Feature for Visualization and User Manual.The stylish look and feel of metal imparts a sense of luxury.