A vellum insert is a semi-transparent sheet that is used to separate the wedding invitation from everything else in the envelope (i.e. reply card, information / map card, etc). This traditional part of a wedding invitation can make even the simplest wedding invitation more elegant. Many years ago, some ink never fully dried; vellum inserts were used so the ink on the wedding invitation didn't smudge onto the other parts of the invitation during the mailing process. Although uncommon today, smudges can still occur due to high pressure and friction in mail sorting machines. We highly recommend vellum inserts.