Mini Magic Solar Calculator with Exquisite Metal Pen Feature: 1, It can be opened and closed in one way direction 2,Metal Pen included. 3,Press"AC/ON" button, then display "o" orperate by "+""-""x""/""="etc. 4,With Function of "M+""M-""MRC" functions 5,Used by solar cell 6,Never need battery 7,Portable with beautiful outlook. 8,It can print customer Logo as wonderful promotional gifts. 9,Which can use it at night time as long as light energ is work as day time.