For your consideration, here is a Vintage 20ths, 32nds, 50^th Inch Increments Plastic Drafting Scale, 6 Inches, made in Japan.  It is not marked with a maker.  The scale has a little wear and light spots on it.  It is marked at MM and CM increments also.  It will be mailed in a box for protection.  Item pictured is the actual item up for sale and comes from a non-smoking household.  (641.9a22d-.5bx2)