3rd Scale Ruler, also has 1:5 & 1:4. Triangle shape plastic with 3 different scales. If you want to test your pattern, this is a good way to save on fabric because you can make your garment small like a 3rd of the size while keeping the proportions the same. Or you can choose either 1:4 ( quarter size) or 1:5 (20% of the original size). Basically a miniature sized garment, to see if you need to make any changes, or you could test the fit if you are lucky enough to have 1:3 size mannequin.
