The working principle of the 3D printing pen is very simple. Everyone can easily draw a three-dimensional picture, her material is used to melt plastic PLA/ABS/PCL. Set the melting point and put the material into the pen. Once the molten plastic cools to the outside of the pen, it will cool and quickly solidify, so that the shape of the extruded filament can be fixed in various shapes. Children can use it to draw with imagination and a sense of accomplishment.