Carhartt's Men's Duck Bib Overall is arctic quilt-lined to keep you warm on the job site. Made of 12-ounce, 100% cotton duck, it is lined with quilted, 100% arctic-weight nylon. It features a zipper fly, multiple tool and utility pockets, a hammer loop, legs that zip to knee and have protective wind flaps, and double knees with cleanout bottom to accommodate knee pads. 12-ounce, heavyweight 100% cotton duck Arctic quilt-lined Double knees with cleanout bottom For the best fit, order one size larger in waist and one size shorter for inseam length. If wearing heavy layers, order two sizes larger in waist.