When the cupsize is perfect but but back is too tight, the bra extender will help you get the exact fit. 3 extension modes: 2,5 cm, 4 cm and 5,5 cm. 100% polyamide. Handwash.

Size S: Width 3.5 cm with 2 hooks
Size M: Width 5.5 cm with 3 hooks
Size L: Wide 7,5 cm with 4 hook