They claim to be 95% cotton.  When I received them I was disappointed to find that they seemed to be 100% spandex.  I have lived a long, life and have an active mind and try to learn a little bit each day.  I think I know the difference between cotton and spandex, and these were mislabeled and now I have sweaty nethers.

On the bright side, they fit very well and seem very well made.  It's just disappointing that they are made from different things than they claim.