Patent attributes
A subrack (1) includes a plurality of plug-in units (50), two parallel sidewalls (10, 20), a bottom wall (24), and a top wall (30). Each of the plug-in units includes a particular combination of code pins (60). Each of the bottom wall and top wall includes a first plate (35). The first plate defines a plurality of spaced slide channels (351) for slidably receiving the plug-in units respectively, and forms a plurality of L-shaped flakes (40) substantially in front of the slide channels respectively. Any one or more of a height, a length, and a deviation relative to the corresponding slide channel of each of the flakes varies relative to another one of the flakes according to different combinations of corresponding code pins, in order that the flakes respectively match the combinations of the corresponding code pins and thereby prevent improper insertion of the plug-in units into the subrack.
