I never in my life have had this happen before. I bought what I was sure would be at least a little snug size-wise (M )and boy was I in for an unpleasant surprise. I got out of the car and stood up, and felt something strange on my knee and my
underwear had
fallen down! These are either so far off in sizing as to be irrelevant, or they have no elastic. I wish I could send back the pair I was wearing as well, but the others are going back for sure!