Ruler with hollow interior - made from plastic hollow profile for insertion of strips with indicators

摘要

The ruler is made either translucent or transparent in at least some of part of it and made hollow for at least a proportion of the length for the insertion of one or more strips (4) of indicators (5). The ruler may be written on and any writing can be wiped off. It is made as an extended plastic hollow profile closed at one end. The ruler as well as the hollow spaced interior have a flat rectangular cross section. The ruler may have two or more hollow spaces (2) arranged in one plane next to each other or set at an angle to each other.