SOLAR POWEREDSince it is powered by solar energy, you can use this calculator whether you are indoors or outdoors, which is not only completely economical but also very convenient.^ COMBINATION OF CALCULATOR & RULER & MAGNIFYING GLASSNot only is it a ruler but alos is a calculator, and it also has a magnifying glass.^ FUNCTIONAL AND COOLGive your math-loving friends a unique gift that combines both scales and has a simple calculator with a large display for general purpose calculations.^ DURABLE AND USEFULMade from quality plastic, this unconventional measuring ruler with 10-digit calculator. It is a necessity for students.^ SIZE13cm x 4.4cm x 0.36cm/5.12" x 1.73" x 0.14" (Approx.). It is very small, cute and easy to carry.