E-pencil / Pencil

E-PENCIL is an automatic pencil which designed for architect designers and product designers.Designers need to know the aspect ratio and size when drawing a sketch .It is very difficult to use a ruler to measure them one by one,after using the E-PENCIL,you can roughly know the ratio of the sketch,which lays a good foundation of the latter work.
There is an internal button battery which acts as power .It uses the people's usually subconscious action---pen spinning ---to scroll the wheel, which installed at the end of the pen,to get the battery charged,in which way the battery need not to be changed.