100% cotton. Brushed flannel twill fabric. Full button fastening. Chest pocket. Buttoned cuffs. Regular fit. Here is the Portland Check Shirt and its nothing short of a twill-based miracle. The hand-feel of that brushed flannel fabric is more aligned with the rind of a stoned fruit than something you could wear in real life and time, and that classic shape and design is prime for all manner of civilian pursuits.