| 摘要 |
A rail assembly includes an outer rail, a middle rail, an inner rail, and a retrieving unit. The outer rail has an outer rail space for accommodating the middle rail, the inner rail, and the retrieving unit. The middle rail slides in the outer rail space and has a middle rail space for accommodating the inner rail. The inner rail is accommodated in the middle rail and slides in the middle rail space. The retrieving unit is assembled on one end of the outer rail space. |
