Between when production started in 1953 and 1961 when it stopped there were very few changes made to the Singer 222K Featherweight. There were a few and this post will show the earliest change.
When production started in 1953 with serial numbers beginning with "EJ" the sew/darn lever plate was different than the stitch length lever plate. They didn't match. The stitch length lever plate was aluminum with a black finish and aluminum markings which was the same as 221 Featherweight plate. The sew/darn lever plate was quite different. It was chromed steel with no markings.
Singer used this chromed plate through the entire EJ series and part way through the EK serial numbered 222K Featherweights.
In mid 1955, part way through the EK serial numbered machines, Singer changed the sew/darn lever plate to match the stitch length lever plate. Singer continued to use this plate on 222K machines until production of 222K Featherweights stopped in 1961.
The chromed sew/darn plate is often mistakenly thought to be not original. It is original on all EJ and many EK serial numbered 222K Featherweights.