| 摘要 |
The fitting part (10) has distant bars provided at groove edges. Two groove-shaped or groove-shaped lateral recesses (11) receive one of the bars in a mounted position. Width of a groove base side portion (13) in a region is smaller than distance between the bars of a fitting part groove. Width of a groove base facing portion (14) in a region is larger than the distance between the bars of the fitting part groove. The groove base side portion and the groove base facing portion comprise edges (15-18) that are diagonally aligned to each other. |
