I just brought home this Singer 206 treadle. The Serial # is C3669668. As far as I can determine it was made in Wittenberge, Germany (Prussia) in the mid to late 1930's. It even has the Manual in German! I'm new to these vintage machines so I've got a huge learning curve ahead of me. I've been able to find out a few things. I found a list that said the C meant it was made in Wittenberge but I couldn't find anything about the serial number. I read that this was Singer's first machine with ZZ and that they rushed it into production because Elna and Bernina were already producing a ZZ. I also found that it uses an unusual 206x13 needle and that if you use a standard 15x1 it may damage the bobbin case. The only history I know is that it was found at a yard sale a couple of years ago after it's owner passed away and that she was an avid seamstress and had the machine "a long time". I'm almost enjoying the history of these machines as much as the opportunity to fix them up a bit and use them. Any information you can add would be greatly appreciated.