Protective device for guiding edges of transparent drawing aid, in which guiding edges are made of more wear-resistant material than body of aid

摘要

The protective device is applied to the edges of a transparent drawing aid, e.g. in the shape of a triangle, bounded by edges (1) and with markings (2) on the upper side. The guiding edges are reinforced with a material which is considerably more wear-resistant than the transparent plastic of which the drawing aid is made.