Just a quick note. A friend of mine used an odd size envy 3" x 6 3/4" (what I thought would be an adequate size-about an 1" longer than a check) and it was returned to her as non-mailable. It was stamped "Return to sender, envelopes and cards less than 3 1/2" x 5" are non-mailable". So, even though only one side was 1/2" shorter than their stated 3 1/2, it got returned. Bummer.
FYI
Annette
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