8.5-ounce FR canvas: a blend of 88% cotton and 12% high-tenacity nylon. FR twill face-cloth lining quilted to midweight modacrylic insulation. Sits slightly below the natural waist. Full seat and thighs. Ankle-to-thigh leg zippers with Nomex FR zipper tape. Inner and outer leg-zipper flaps with arc-resistant snap closures. Double knees with cleanout openings to accommodate knee pads. Reinforced leg-bottom kick panels. Two reinforced back pockets. Triple-stitched main seams. Carhartt FR label sewn on back pocket. HRC 3 label sewn on front waistband. NFPA 70E compliant. Flame-resistant fabric by Mount Vernon Mills.