I bought two pairs of the black cotton full coverage undies awhile ago, then put them aside and forgot about them. Recently opened one package and I see that they are cotton/elastine, not 100 percent cotton. The fabric is a little thick, but I suppose that is for the structure and the support of the pouch in the built-in pocket. I don’t think these are for me (a plain loose cotton Granny wearer) and it is too late to return. If anybody here would like them I would be happy to give them to you. Just send me a message. One is in a sealed package, the other only taken out of its package one time, never worn. They look like they run true to size. The fabric has some stretch (the elastine) that I think is so that they will fit smoothly and support the pouch.