THE BEST for headlights "on" problem.  They cover the whole breast, perfect smoothness, without adding bulk.  When I slip these in my bra I have total confidence that my nippies will not be saluting..  No more worries, you can wear anything.  It's a huge confidence booster. They are large, and so I think a C cup or more will benefit most.  Probably too much coverage for small breasts.  I am DD and praised God when I found these things.  Wish I'd found them sooner!