Here is the latest machine, a beautiful Singer 201K treadle manufactured in 1936. I had a devil of a job trying to get decent pictures today - poor light, reflections, etc. etc., but I'm sure you get the general idea... The only job I have left to do is to get a new treadle belt. The old belt on it is a bit stretched and keeps slipping. The easiest way to spot a 201 is to look at the spool pin. There should be a long, round-ended metal plate beneath the spool pin, which has holes in for oiling. The needlebar comes down from inside a steel tube. The needle has to be threaded from right to left, and the needle is set into the needle clamp with the flat side to the left. And here is a nice loving arty shot of the needle reflected in the plate underneath. It is time I concentrated on my sewing.