Here’s an interesting pair of red ruby celluloid handle knives from 1994.  These coke bottle shaped 50 pattern knives are from the Case Classics series and only 17 pieces total were made in the run. The tang stamp on the top knife shows 71050 as you would expect for a celluloid Classic.    BUT, the model number tang on the second knife is 51050, denoting a stag handle in error.  So, there are two variations in this 17 knife run for collectors to look for.  Remember KnifeDB.com tries to answer all your questions.