[CousinRose]

There was a roll on that came with the Brava system but I've heard some girls getting prep-wipes that do the same. You put it on the skin, let it dry for a few minutes and than you put the domes on. It helps to create a seal! I don't know of any alternatives to it but "it stays" sounds like it could help create a seal. I can't make a seal unless I have the roll on.
The roll on is marked with "Brava".