Sizes are M and L. I bought both to compare, but I didn't feel much difference in size. L size felt similar to M. I wore them for six months. They haven't stretched, so you can still use them. I recommend them because they don't constrict under the bust. I bought other innerwear at stores like Nishimatsuya and Akachan Honpo, but these were the most durable and easiest for breastfeeding. I mostly used them without nursing pads because they provide some support. Belle Maison Innerwear Belle Maison Nursing Camisole Nursing Innerwear Maternity