Greetings Ani: Always ask the serial of any Edison item. I ask the serial of the reproducer to see if it is all original. Many of the O potmetal tops have been replaced by reproductions with no serial on them. When an eBay seller says "brass top O" and answers that there is no serial showing it is one of the reproductions that have been made. Nothing wrong with that but it should not go for the same price as an original. Paul Baker's excellent reproductions have his initials flanking a number so there is no attempt at passing a fake off. The serial on an Edison phonograph will also tell you if a machine is a put together job. Right now on eBay is a Triumph A in a B cabinet with an O reproducer that was on eBay about a year ago. For a new collector who wants authenticity and will pay top dollar for it this might not be the machine for him/her. The serial will delineate models in many cases. Edison had so many interchangeable parts that a mix and match machine can be easily made. Some were even done during the period of production. But, most serious Edison fanatics would rather see all the parts match. The serial helps with that determination. Steve is the king of Edison reproducer research. I am most impressed by his knowledge. He is quite correct about the nature of an Edison reproducer. They were made in the same vein as watches and clocks with similar tools. Hence they were assigned a serial number. I am currently attempting to reverse engineer them and find them fascinating with a lot more going into them than one might expect. Regards to All on the list, Al ************************************** Get a sneak peek of the all-new AOL at http://discover.aol.com/memed/aolcom30tour