Ideal for precise and technical drawings, the Linex Aluminium Tri-Scale Ruler features a triangular shape with a range of scale measurements It has colour-coded inserts and quick scale selections Made of tough aluminium, it includes scales of 1:1, 1:2, 1:5, 1:20, 1:50, 1:100, 1:200, 1:500, 1:1000, 1:1250 & 1:250.