Greetings everyone. I would like to tap your collective knowledge on something I am trying to understand. I purchased what appears to be a Louisville Slugger vault bat (i.e., a prototype). The model number A80 is stamped on the knob and it is also stamped on the end of the bat. Appears to be the same font type / style from model number stampings from the 40's/50's. No LVS center brand logo is present and there is not a player name burned into the barrel. There is very faint writing on the barrel, but so old and faded that it cannot be interpreted. I did some research, thanks to the info provided in Vince Malta's book, and discovered that in 1952 Luke Appling had a new model made (A80) with the same length and weight as my bat. So, I thought this was the prototype Appling bat from the vault. However, I see that an Appling A80 is currently for sale on eBay by Zanes Bats, and that A80 has a completely different knob style than my A80. I am left to wonder what is the deal with my bat? Does anyone know of instances where a vault bat does not match the style of a game used bat of the same model number? Any info or insights are appreciated.