Mr. Pen solar scientific calculator gives you reliable, advanced calculating with a clear 2-line screen and dual-power convenience for school and daily study. Professional-grade capability — includes 240 scientific functions for advanced math and science work. 10+2-digit widescreen HD display — easy-to-read numbers and calculations for quick checking. 2-line display — shows your entry and the calculated result at the same time for fewer errors. Great for fractions & statistics — built for high school, college, and everyday coursework. Protective hard cover — helps prevent scratches and dings in backpacks and desk storage. Dual-power source — runs on a solar panel (works only when it is bright) plus battery for dependable use.