Specification: Item Type: Calculator Combined Size: Approx. 160 x 78 x 13 mm / 6.3 x 3.1 x 0.5 in Expand Size: Approx. 160 x 158 x 7 mm / 6.3 x 6.2 x 0.3 in Battery: Button battery CR1220 120mAh (Battery Included) Working Temperature: -10-40℃ Material: ABS Function: Writing tablet + calculator Weight: Approx. 144g / 5.1oz Color: Black Package List: 1 x Calculator (Battery Included) 1 x Pen 1 x Manual ★ Desktop Calculator With Notepad - This calculator is combine with LCD writing board. With the stylus pen behind of the writing board, convenient for taking notes on phone calls, quick notes, and meeting minutes. ★ Solar & Battery Dual Power Design - This is a solar and battery dual power financial calculator(battery included),it can be fully powered in any lit environment. Stable in performance and easy to operate, so you can use it with confidence. ★ Versatile Scientific Calculator - This writing tablet calculator is widely used in many situations, such as office, business, household, college school, study room, etc. ★ Folding Portable Calculator - This is a lightweight calculator with writing tablet,foldable design, weighs only 5 oz.It is so compact that you can carry it in your pocket,can be quickly removed and used immediately when needed. ★ Eco Friendly Material - College calculators for students is made of high quality ABS environmentally friendly materials, which is durable, wear resistant, and can be used for a long time.