CHICAGO, ILLINOIS -- Although they make shirts in different materials (cotton and cotton/poly) they don't allow you to select this on your order when using the website. In my case, they randomly use one or the other to make your order. Be sure you CALL them and tell them what kind of material you want them to use. Maybe call them twice, because even after you call they sometimes mess up your order.
Better yet, go somewhere else for your tshirt needs.