? ABOUT PROOF SETS

.
did the proof sets always come in a plastic case ?
I have 5 ????? Proof sets that the card in them states they are proof sets, but they are in an envelope with a clear covering that is flexible like a piece of paper.
they are:
1 1961
2 1962
2 1963 sets
there is one sheet in each package.
I don`t remember the mint mark.
what do I have mint sets or proof sets ?
.
did the proof sets always come in a plastic case ?
I have 5 ????? Proof sets that the card in them states they are proof sets, but they are in an envelope with a clear covering that is flexible like a piece of paper.
they are:
1 1961
2 1962
2 1963 sets
there is one sheet in each package.
I don`t remember the mint mark.
what do I have mint sets or proof sets ?
.