It was cotton if it was white, don't remember if that was a 2 1/2" or a 3" strop but both use a slightly different weave of cotton, the 3" being a more coarse weave and thick, the 2 1/2" a finer, firm weave. The grayish/tan is the flax linen.@Tony Miller. Do you know off hand which secondary you put on that steerdovan I won. It is the white secondary and not the grayish one on your site. I'm curious as to which because as a secondary I love that one but now am curious as to the flax as it was said it has silica in it so makes a good secondary.