The 12 inch Flatback looks older. It has additional writing on it, later Flatback 12 inchers only had "EAGLE SIGNAL" on the back. The bottom two sections are 1970 Eagle Flatbacks.
Your welcome. I have a 1960 Eagle Flatback. Which actually had "trapezoid" shapes on top and below the Eagle logo. 1950 Eagle flatbacks had rods holding them together. Those you can tell easily, they have bolts on the top and bottom on the signals bodies.
Cool signals, where where all of these? (I assume all of these 5 shots where at the same intersection) BTW the plumbizer is made by Powerlite and is still made by Alstruct today
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