Old Pontiac light?

Can anyone share some info on this light set????

 

Is that an early car brake light, one of those deals that changes colors or has turn signals built into it? The nameplate looks like it could be changed to show any make you wanted.

 

It has (3) 6 volt bulbs in it. We're guessing in the 20's. Need as much help as we can get!!

 

Change the name to Bugatti , put it on Ebay and enjoy the result.

 

Weird but cool. The blue lense has SLO in it. I can't tell if the left lense is frosted clear or steel.

 

I bet it is an aftermarket unit. Any casing marks or numbers on lenses?