What do you bring to a seder?

A passover seder is a religious event and you would normally wear the same type of clothing that would be worn to the synagogue or at a sabbath meal.

Guests who are not familiar with religious customs can wear any nice outfit (maybe with a sport jacket), though tee shirts, jeans, tank tops, tight shorts and outfits with decolletage are not appropriate in religious circles and will result in polite stares until others at the table get used to the fact that you are really a nice person.