The Coverall GWM features a waistband with elastic inserts for flexibility, double knee patches to reinforce strength, a covered front zipper and ankle to waist zippers. The shell is composed of durable and comfortable 60% cotton/40% polyester brushed twill, with mid weight polyester insulation. The Grow System allows sleeves to extend an additional 1-1/2 inches after the special stitching is released. Material: Cotton, Polyester, Twill.