For your consideration, here is a Vintage Bellingham Blueprinting Company Plastic Drafting Scale, no. 8501, 6 Inches.  The scale has some wear on it.  There is a name engraved on the right end of it.  It is marked at 1/8, 1/4, 3/8, 1/2, 3/4, 1, 1 1/2, and 3 inch increments.  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.  (635.7a30a-.5bx2