These were the first buttonholes I got so having a mix was perfect. You really have no way of knowing what sizes go on your shirts unless you have multiple corset options to compare. So ideally it would be better to buy more corsets in specific sizes (there are very few of some types). box) , I would not have been able to know without this variety. I put corsets on when I put on a shirt and take them off when I remember, so the limited number of corsets in each size isn't a big problem. Be sure to give your collar a strong shape