Simplex Time Recorder 624-181 Questions

[thun_derbolt1000t]

Hello all, I have recently acquired a Simplex siren, model 624-181 (Federal 1st gen model A). My questions are about when these sirens were made and the differences between the Federal Signal, Farday, and Benjamin Co. versions. I would also like to know if any of the different company versions are rarer or if they are about equal in collecting value.
Thank you!


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Owner of a Federal Sign and Signal Model 5, Model D, Model L, Model RX, and a Simplex 624-181

[Model L]

I do not believe that there are any functional differences between any of the rebranded versions. they are simply just rebranded units all manufactured by federal signal.