Numbers on the back are either the factory pattern number or the shape number !! Many factories used either one or the other and some used both !! That does not help with the pattern name unless you know which factory out of hundreds made it !! I would suggest going to replacements.com and use their matching service !! Look on the home page,, the service is free !! Of course they hope you will buy your extra pieces from them !! They are usually overpriced !! Ebay is better when you know the mfr and the pattern name !!