Rockeroo Boutique Its My Birthday Bitches Rhinestone Womens Tank Top Tee Shirt Size Small fits size 0-4 - chest size A cup, Medium fits size 4-6 - chest size A or B cup, Large fits size 8-10 - chest size B or C cup , XL fits size 10-12 - chest size C or D cup, XXL fits size 14-18 - chest size C or D cup.