Carhartt"s canvas shirt jac is flannel-lined for extra warmth. Made of 9-ounce, 100% cotton canvas, it features a 4-ounce, 100% cotton flannel lining, antique-finish brass snaps and two chest pockets with rivet reinforcements. Main seams are triple-stitched for durability. 9-ounce, 100% cotton canvas 4-ounce, 100% cotton flannel lining Triple-stitched main seams