The Detroit & Mackinac Quad Hopper Car No. 6736 was produced from 1960 until 1962, and was RED in color with WHITE lettering, center brace, but no covers. Came with early AAR trucks that had disc couplers. There are two variations:

Variation A: As listed above.
Variation B: Has a WHITE "blotch" of paint on the face of "Mackinac Mac." This is a common factory error due to an imperfection in the heat-stamp die, and this car is even illustrated with this flaw in the 1961 catalog.