Contrary to reviews I read here before purchasing, the waist size runs small.  I have a 31" waist so I ordered the small and had to return them.  I replaced with medium which fit me perfectly -- the medium fits snug without drawing in any on the waist cord.

To my pleasant surprise, mine were 100% cotton, contrary to product description of 60/40 cotton/polyester.  The fabric is lightweight but does not seem to be easily damaged.

I then ordered several more pair which also came 100% cotton.  All my orders were from Amazon itself as the seller.