Just imagine, anytime, anywhere, even from a distance, you could control a pen with your mind. It could roll back and forth freely on a hard, smooth surface, and stop at any position at will. How incredible is that? "After hundreds of days and nights of effort, we have achieved a highly integrated design with no openings in such a narrow pen barrel space." We've finally made it happen.！ "Just need to bring a Sharpie when you go out, no need for anything else!"