| 摘要 |
<p>The device has a base associated with a rear support unit (40) that includes a support side (47) opposite to a free side (48). The unit (40) is rotatably mounted with respect to the base. A toe piece (60) has a slide (72) movable along the rear support unit and a unit for immobilizing the slide on the unit (40). A rear wall or support (90) covers the slide on the side of the free side. The immobilization unit traverses the wall.</p> |
