| 摘要 |
<p>The curb (1) has a longitudinal groove (3), and a transversal groove communicating with the longitudinal groove. The transversal groove is opened on a proximal longitudinal edge of the curb, where length of the curb is between 30 and 100 cm. Intersection of an upper surface (2) and the longitudinal edge of the curb forms a round line. Width of the longitudinal groove is between 10 and 30 cm, and depth of the longitudinal groove is between 10 and 20 cm.</p> |
