Bulwark Flame Resistant 5.25 oz Cotton Dress Shirt 88% cotton, 12% nylon Made in the USA or Imported No Closure closure Lined, topstitched button down collar Topstitched cuffs with adjustable button closures Placket front with button closure Fabric made of 5.25 ounces, 100 percent cotton Arc rating ATPV 5.5 calories/sq cm