Size A: For light/medium menstruation and if you have not yet had a baby.
Size B: For medium/heavy menstruation and if you have already had a child via vaginal birth.
Size A : Diameter = 4,0cm - Stem length = 2,0cm - Cup length = 5,0cm - Total length= 6,6cm - Volume = 25ml
Size B : Diameter = 4,5cm - Stem length = 2,0cm - Cup length = 5,2cm - Total length= 7 cm - Volume = 30ml
In this case it is B, another size can be found in another article, for example A : OrganiCup Cup menstruelle, taille A (1x)
Unfortunately, this information is missing in Italian, but if you put the site in France, for example, you will find the size in the name of the article.
The problem is that the article is unfortunately no longer visible when assembled. In addition, most product pictures are taken before use and not during use, the best example being nappies and toilet brushes.