Old Navy Reversible Square-Neck One-Piece Swimsuit With teal on one side and this tie-dye option on the other, the Old Navy Reversible Square-Neck One-Piece Swimsuit ($40) is a perfect match for the seaside. Image Source: oldnavy.gap.com Old Navy Reversible Square-Neck One-Piece Swimsuit $40 from oldnavy.gap.com Buy Now