| 摘要 |
A board for writing by means of a pen producing erasable marking comprises a header (2) fixed to it by means of a hooking device which permits the header to be removed from the board and hooked again an infinite number of times without damaging any part of the header or the board. The hooking device consists of wings (7) which act as a guide when the board and the header are assembled, a pair of elements (8) of inverted "U" shape which are inserted into a pair of openings (6) located in the board. |
