Carhartt Flame-Resistant Long Sleeve Mock Turtleneck Shirt Modacrylic / Cotton 6.5-ounce FR knit: a blend of 55% modacrylic and 45% cotton Rib-knit turtleneck collar and cuffs Side-seamed construction minimizes twisting Left chest pocket with Carhartt label Carhartt Flame-Resistant and CAT 2 label sewn on left-chest pocket.