John:
There were 2 basic o/u models as Pete stated. The 1500 which was built in Spain by Aramberri. And the 1000 which was built by Beretta. The 1500 was pretty much a Perazzi copy and is the grandfather to the Kemen KM-4 as well as a dead ringer for the AYA MD-2. I own a model 1500 that I picked up at an auction several years ago for not much money. I've been trying to find out about info on the gun since there's so little that's out there.
The 1000 I don't know much about other than it was a re-badged Beretta. I hope this helps some.
Parris George
