... operation; 5. Quick and easy USB cable connection to PC and PC and be made in the whole machine; 6. No external power supply is needed ... you to write, move, rotate, zoom in/out object and shift page, etc. with your finger instead of e-pen;Adopt 6 ... be recognized by pens, ruler, protractor, set square, searchlight and other tools, and to page up/down, drag object, clone object, etc. Also ...