Combination of scientific calculator and writeboard, stylus hidden behind the calculator, calculate and record at any time, effectively improve learning and work efficiency, clear 12-digit display for easy calculation. It contains 240 mathematical calculate functions which covers basic calculate, scientific function calculations, etc. Double-line display screen design, the first line shows the calculation process, the second line shows the calculation result. Press the clear key to erase the LCD notes and protect personal privacy. Special one-key lock function can prevent important information from accidentally being deleted. Note: Please make sure that -key lock is unlocked status, otherwise you will be failed to clear the writing tablet. The desk calculator is powered by CR2025 battery, it can be replaced at any time. Working time:12-18 months, stand-by time:18-24 months; saving energy and longer stand-by time, no need worry about low battery power. Scientific calculators use blue matte LCD screen to protect the eyes, The writeboard text can also be read clearly in the sun. Paperless environmental protection, repeatable writing. color: Blue Material: silicone, + plastic Package Contents: 1 x calculator Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.