For example, if while designing a spark plug, a 3D model and drawing of that component was created, and minor changes were made to that part , the 3D model must automatically change its dimensions in order to adapt to the general trend. Bidirectional associativity therefore consists of making adjustments to the component from the drawing mode by modifying the dimensions presented on the drawing, thus causing the 3D extruded model of the component to be updated. This is an extremely useful feature that allows you to adjust the size of components at each stage of modeling, without the need to apply a patch in another..