Plain color 100% cotton. Wine Heather, Ocean Blue Heather and French Navy Heather colors 80% cotton / 20% polyester. Grey Heather 70% cotton / 30% viscose. All colors are made from organic cotton fiber. The OCS certificate (Organic Content Standard) is issued by Ecocert Greenlife. Ribbed collar and bottom sleeves 1x1. Tone on tone 3 button placket. Herringbone band finish on inside collar and side slits. No brand label on collar, only a size chip for easy customization.