①. Easy to use: The scientific calculator makes it easy to solve the most complex math problems, equations and scientific formulas, making it a useful tool for both students and professionals. ②. Dual power supply: This portable school mini calculator has a dual power supply system with a built - in solar cell, a reliable 3 - week battery and 3 weeks of standby time. ③. Versatile use: The multi - function calculator is suitable for solving a variety of math problems, from GCSE and A - level exams to higher level studies, helping users be prepared for many challenges. ④. Comprehensive functionality: With just a few steps, this multi - function portable student calculator can perform complex calculations, logarithmic and integral solutions to meet various needs. ⑤. Advanced functions: The scientific vector test calculator is designed with advanced functions to perform vector calculations and scientific research, being a versatile and useful tool for students and professionals. ⑥. Note: The appearance of different batches may vary slightly, which does not affect the use. ⑦. Color: Black ⑧. Contents: 1 * Scientific Calculator. Only the above package contents, other products are not included. ⑨. Note: Due to light reflection and different displays, the color of the item in the picture may be slightly different from the actual item. Please allow +/- 1 - 3cm error due to manual measurement.