Architectural — Plastic 12" scale divided in 3", 1-1/2", 1", 3/4", 3/16", 3/32", 1/2", 1/4", 1/8" to the foot. One division in 16 parts to the inch.
Engineering — Plastic 12" scale divided in 10, 20, 30, 40, 50, and...
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