FC991esplus 4nd Scientific Calculator, featuring 417 functions, a slide-on hard protective case, and CR2032 battery power.

1. **417 Built-in Functions**: This scientific calculator features 417 built-in mathematical functions—including support for complex numbers, matrices, vectors, base conversions, statistics, trigonometric functions, and table calculations—meeting the diverse computational needs of algebra, physics, and engineering courses.

2. **10+2 Digit High-Resolution Textbook-Style Display**: Equipped with a large, high-resolution dot-matrix screen, it displays formulas exactly as they appear in textbooks. The clear display helps reduce eye strain during long study sessions and makes it easy to read and verify calculation steps.

3. **Responsive and Durable Plastic Keys**: Features high-quality plastic keys that offer quiet, comfortable operation and precise tactile feedback. They are wear-resistant and durable, making them ideal for the frequent, prolonged use required by students.

4. **Scratch-Resistant Slide-On Hard Cover**: Comes with a textured slide-on hard cover that protects the screen and keys from scratches, bumps, and dust. Its compact size (167×82mm) makes it easy to carry in a schoolbag or pencil case.

5. **Reliable CR2032 Battery Power**: Powered by a CR2032 coin-cell battery, it delivers stable performance and supports extended use. It is an ideal tool for middle school, high school, and university students for homework, classroom study, and exams.