Chengdu Mingzhihui Consulting Co.ltd is a selling world first Music Electronic Teaching board in Europe. The company has the property patent of type and appearance of the product. â??Music Electronic Teaching-boardâ??, the patent product not only retains the ferula demonstration function of musical staff, but also integrates staff, key signature, tune name, keyboard, and many other elements of music theory. In addition, it connects the above elements cleverly by using sliding scale; finally, it realizes the visibility and intuitionism of music theory, and full demonstration of music theory.