13-ounce, 100% cotton FR duck. 10.5-ounce FR quilt lining: FR modacrylic batting quilted to twill face cloth. Two large, quilt-lined front pockets. Inside patch pocket with hook-and-loop closure. Nomex rib-knit collar. Brass front zipper with Nomex zipper tape plus inside and outside protective flaps with covered snaps for electric-arc protection. Carhartt FR and HRC 4 labels sewn on left-front pocket. NFPA 70E compliant. Flame-resistant fabric by Mount Vernon Mills.