класс ручки

The advantage of the class teaching pen: 1) The liquid chalk ,as we term it,uses its body structure hold the ink ,and with an automatic valve controls the liquid flows directly and easily. 2) There is large reserve supply of ink, a fast flow and the ink is completely protected in the pen . 3) This product can be refilled with ink,and the nib can be replaced.it can be re-used all the time for 100% effective use,so the comprehensive cost is low. 4) Works like a Marker Dries like chalk ,4 colors(white,yellow,red,blue) you can choose,colors also can according to the customers’ requirements.