| 摘要 |
<p>The element (10) has two brackets (11, 12) arranged at an angle to each other and flexibly connected with each other in a detachable manner. A surface of one of the brackets has guide rails parallel to lateral outer edges, and bars are provided between the guide rails and run parallel to the guide rails. The brackets are respectively provided with round and elongate holes, and have projections (13, 14) engaged with each other. An opening angle of the element formed between the brackets is freely adjustable.</p> |
