| 摘要 |
<p>A leveling element comprising a post, a support plate containing an opening defining a seat for receiving an end of the post, bearing means at said end of the post structured to be received in said opening in engagement with the seat for angular movement of the support plate relative to the longitudinal axis of the post and yieldably retaining means incorporated in the opening yieldably displaceable to permit the bearing means at the end of the post to be moved into the opening into engagement with the seat and to retain the support plate at said end of the post.</p> |
