Federal Signal 351, 352, 451 and 452 horns. Had they existed?

So I was looking through all the alarms mounting info and specification papers I had and I found a mounting sheet that I had recieved with a Federal Signal 450-048-001(48 VDC 450 B1 Series) and backbox and I stumbled on a description below where it says:

Vibratory Horn Instructions (See below):
[attachment=0]Federal Sig Mounting Sheet.jpg[/attachment]
So now I ask: Are those horns (in the title) real? Do 351’s and 352’s look like 350’s of the B1 Series? Do 451’s and 452’s look like 450’s of the B1 Series? Were they all prototypes that didn’t pass the bar? Or is it a mystery the world may never know?

One other question: Does the Simplex 4048 have any part in a rebrand of one of the 351’s and 2’s?

(BTW I reposted the picture of the 4048 from the Rare fire alarms topic)
[attachment=1]Simplex 4048 Horn.jpg[/attachment]

If they were in the spec sheet, they once existed. I’ve never run across them though. Usually, model numbers like that are minor variations of a greater series that differ in mounting, voltage, or color, etc. I’d say there’s a good chance that the Simplex 4048 was a rebranded 351 or 352, but that’s just a guess.

The 4048 looks to be a flush-mount variation that was probably phased out since the regular 350 could just as easily be put behind a flush mount plate. Sometimes companies will consolidate overlapping product variations to eliminate separate moulds for manufacturing.

Thanks. That could just be it. It all in a way adds up. Not to mention most of the equipment Simplex has rebranded from Federal Signal, usually has the label riveted in.
[attachment=1]Simplex 4040 Label.jpg[/attachment]
[attachment=0]Simplex 4048 Label.jpg[/attachment]