Use this ProSeries compatible self seal envelope with your ProSeries generated slip-sheet. This First Class Mail Portrait envelope with double windows is designed specifically for your ProSeries software. It is 9.5” by 11.5” and is available in a moisture seal version ProSeriesPEL12. This envelope is also compatible with the ProSeries folders see items ProSeriesSFGR14, ProSeriesSFDB04, ProSeriesSFG24 and ProSeriesSFR34.