Either a 1940's FedElCode Model 2 or an H.O.R. Siro-Drone.

I've been thinking of making my own siren picture database, since the Siren Archive hasn't been updated in years.
One that is on this site would be great!

The rounded T-bolt always had a square horn. The blower and rotator box were slightly rounded off at the edges. I don't think any were produced; it was probably just a prototype spotted in an old advertisement (Companies tend to show prototype models in advertisements for some obscure reason.)

There are two Hurricane 130's that come to mind, the one that Crazywarriorman used to own (from Centralia, Il.), and there was one in Baxter, Mn. that disappeared years ago. The 550AT is also pretty rare. However, I know of more 550AT's than I do Hurricane 130's. Let's see...Calhan, Co. (still used)...

It could be either. It looks more like a 2802, but my Whelen knowledge is limited.

Thanks! Here's a couple more... http://imageshack.com/a/img547/3126/a7gy.jpg ??? I have no idea http://imageshack.com/a/img24/2826/hig6.jpg appears to be a Darley but doesn't look like the model 5 we just ID, after these I'll have all my mystery sirens identified, so I guess I'll have to go out and...

See if you can acquire that rare bird! Too bad it was replaced, but at least it wasn't replaced with a 2001!

That's not a Model 2, it looks to be a Model 5 or 7 with a customized housing...

^H.O.R Omnidirectional.

As for dating, they have to be made before 1952 (when they changed the name to Federal Sign and Signal.)