Because Comexim is a Polish brand, the cup sizing is not going to exactly correspond to traditional UK brands (like Panache, Freya, Elomi, Curvy Kate, etc). The size listed IS UK sizing, but Comexim bras run about two cup sizes small compared to these UK brands. SO, for a fit that is technically correct and gives adequate wire coverage on the sides, you should order two cup sizes larger than you do in your regular UK styles. For a little extra oomph, only order up one cup size, especially if you have an empty/shallow upper bust - but keep in mind this will make your swim top less able to completely contain you.
The Comexim Vivien Padded Plunge Underwire Bikini Top (CMVIVIEN) is a beautifully vibrant sexy swim top with underwire for a high, rounded shape. This bikini top has multi-section underwire cups that separate and define, in an abstracted watercolor-style pattern sure to catch the eye. Features adjustable shoulder straps. Pair with the Comexim Vivien Bikini Swim Bottom (CMVIVIENBB), sold separately, for matching swimwear style.