| 摘要 |
<p>The height adjustment structure (1) has intermediate portion (3) such as channel that is arranged between base and gutter portion (36,40). The spacing (a) between intermediate portion and base is adjusted by screw (4). The intermediate portion is provided with fold (19) for holding screw head of screw. The intermediate portion is provided with apertures in bottom to connect intermediate portion with gutter portion.</p> |
