Since I didn't go on any beach trip, I just tried on my Shell Halter Top at home. I made this 15 yrs ago and it still fits! This summer top is a classic and never goes out of style.
I used our local Cannon size 8 cotton threads, and it may be substituted with size 10 cotton threads, since the hook size is 2mm.
Pattern and details available on Ravelry, and on Etsy.