Wow. I thought the model no. meant the hp that the siren motor had. That is pretty cool. We really have found some great info about a lot of stuff.
I'll just add this to my siren dictionary stored in my mind.
"And they think it will make their lives easier
For God knows up 'til now it's been hard..."
-Eric Woolfson
Owner of several small sirens, a botched Darley 7T, and a 2001 Roundback.