Congratulation Wording For Wedding Wedding Card: Giving One When They Will Be Picking Up The Registry Gift Themselves?

Wedding Card: giving one when they will be picking up the registry gift themselves? - congratulation wording for wedding

I am invited to a wedding and bought the pair for recording. But I will not make the wedding because they receive the gift shop. So do not go to "empty hands" for the party to give them a card? I tell them a card anyway just so they know they want their gift and is ready for pick-up? How could speak, even on the map? When I am afraid to give them to a card that will be confused as a sum of money.

I'm confused! What is the protocol?
Thanks