Great light/siren! I prefer the PropelloRay to the SolaRay any day. Just curious, does the label indicate the rear light (78BR)? Regardless, a great find and excellent addition to your collection.
Back in the 40s/50s when these were first used, it didn't take much to get motorists attention, and these were like all-inclusive lightbars of the 70s. The dual tone (frequencies) of the siren was meant to be heard by even the most hard of hearing. So I would say, yes, Federal was thinking of design and innovation. In 50 years, we won't be driving anyway and self driving vehicles will automatically yield to emergency vehicles!
Here's mine (also restored by Sirenman) displayed in the garage where I can wind it all the way up (with ear protection of course)!
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