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 / 5.1ozColor: Black Package List:1 x Calculator (Battery Included) 1 x Pen1 x Manual [With Writing Tablet] The combination of a standard function desktop calculator and a writing tablet, can effectively save your pen and paper, and you can calculate and record what you want. [Folding Design] This solar calculator adopt folding design, which is lightweight and easy to carry, can be put in bag, pocket, or even purse, [Eco Friendly Material] Made of high quality ABS environmentally friendly materials, which is durable, wear resistant, and can be used for a long time. [Stable Performance] With exquisite workmanship, non toxic and harmless, safe, stable in performance and easy to operate, so you can use it with confidence. [Widely Application] This writing tablet calculator is widely used in many situations, such as office, business, household, school, study room, etc.