Pen and the pen cap are always used together, "Tumbler" pen cap combines the design of scale through visual sense, tactile sensation and auditory sense to redefine a new way of communication, to let people rethink the meaning of "paint". The tip of the cap will jut out, so you can use your thumb to push it with less energy and you can also easily unload or put on it. In the design of the pen cap, we use a special color material with different thickness.In addition, the pen cap is arranged according to the different collocation of colors. When the pencil lightly crosses,some different tones of crisp sweet music will come out. According to the different thickness of the pronunciation point, 12 pens will have 12 different caps with different colors. The "music" pen cap can not only exercise the player's patience, but also serve as a creative toy for children, stimulating their auditory development, developing their perception of music, and maintaining their interest in painting.