From website: FLAME-RESISTANT CLASSIC TWILL SHIRT Description Men's button-down shirt made of durable flame-resistant twill. Designed to handle the most rugged working conditions, this men's button-down shirt keeps you safe from dangerous arcs and flame. It's made of FR twill, with durable triple-stitched seams. The utilitarian design features two flap pockets on the chest. Features 7-ounce, 88% cotton / 12% high-tenacity nylon FR twill Meets the performance requirements of NFPA 70E UL® classified to NFPA 2112 Carhartt FR label sewn on left pocket; NFPA 2112/CAT 2 label sewn on sleeve placket Carhartt-strong triple-stitched main seams Button-down collar and front; Flame-resistant melamine buttons Extended sleeve plackets with adjustable two-button cuffs Two chest pockets with flaps and button closures Brand new with tags; never worn