Ariat Men's Flame Resistant Work Shirt 88% Cotton, 12% Nylon Imported Pull On closure Machine Wash Meets the Hazard Risk Category rating of HRC 2 Rated over 9 in Arc Thermal Performance Value ATPV 9.5 FR Durable soft twill that is comfortable against your skin Clearly labeled per OSHA requirements as FR and HRC2 NFPA 70E and NFPA 2112